Cementitious reagents, methods of manufacturing and uses thereof

ABSTRACT

Described are cementitious reagent materials produced from globally abundant inorganic feedstocks. Also described are methods for the manufacture of such cementitious reagent materials and forming the reagent materials as microspheroidal glassy particles. Also described are apparatuses, systems and methods for the thermochemical production of glassy cementitious reagents with spheroidal morphology. The apparatuses, systems and methods make use of an in-flight melting/quenching technology such that solid particles are flown in suspension, melted in suspension, and then quenched in suspension. The cementitious reagents can be used in concrete to substantially reduce the CO2 emission associated with cement production.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of U.S. application Ser. No.17/369,486 filed Jul. 7, 2021, which is a Continuation of U.S.application Ser. No. 17/127,936 filed Dec. 18, 2020, now U.S. Pat. No.11,174,199, which is a Continuation of U.S. application Ser. No.16/915,804 filed Jun. 29, 2020, now U.S. Pat. No. 11,104,610, whichclaims the benefit under 35 U.S.C. § 119(e) of U.S. ProvisionalApplication Ser. No. 62/867,480, filed Jun. 27, 2019, U.S. ProvisionalApplication Ser. No. 63/004,673, filed Apr. 3, 2020, and U.S.Provisional Application Ser. No. 63/025,148, filed on May 14, 2020, thedisclosures of which are incorporated, in their entirety, by thisreference.

BACKGROUND

The field of the present disclosure is related to cementitious reagents,and more particularly, to the creation of relatively homogeneouscementitious reagent materials and cementitious materials from abundantheterogeneous feedstocks.

Concrete has played an important role in civilization for thousands ofyears and is still the most commonly used building material. Cement isthe essential binding component of concrete that allows flowableconcrete slurries to harden into a useful composite material at ambienttemperatures. Many binder chemistries have been successfully used tomake concrete, but Portland cement and its variations have been thedominant concrete binder for almost 200 years. Despite advances inproduction efficiency and material performance, there are significantand intrinsic problems with Portland cement chemistry that cannot besolved at any reasonable cost by current methods.

Portland cement production is a CO₂ intensive process that causes about8% of global anthropogenic CO₂ emissions. Some estimates project thatcement demand will increase by 12-23% by 2050. However, the growingabsolute demand for cement is at odds with the need for completedecarbonization of the economy that is also required by 2050 to avoidcatastrophic effects of climate change, according to the UN IPCC ClimateReport 2018. There is therefore an urgent need for drastically loweringthe specific CO₂ emissions of cement, especially because absoluteproduction volume is increasing.

One way that the industry has tried to reduce the CO₂ emission of cementis by developing geopolymer cements, which are generally aluminosilicateinorganic polymer that cures through a geopolymerization process.Commercially relevant geopolymer cements in use today require access toseveral specific solid reagents (commonly: metakaolin (MK-750), groundgranulated blast furnace slag (GGBFS), and coal fly ash). However, thesereagents cannot satisfy the global transition to low-CO₂ cements becausesupply is relatively limited in geography and volume compared to theenormous demand for cement. Also, the cost of shipping these productsfrom production locations is significant compared to their market value.

Cementitious reagents are useful in both hydraulic and geopolymercements. Geopolymer reagents, and supplementary cementitious materials(SCM), are typically selected from several common cementitiousmaterials: byproduct ashes from combustion (e.g. coal fly ash), slagbyproducts (e.g. ground granulated blast furnace slag), calcined clays(e.g. metakaolin), and natural pozzolans (e.g. volcanic ash). Thesematerials are generally substantially non-crystalline and sometimesreactive in cementitious systems such as in geopolymeric systems.

Since the majority of SCMs that are used in blended hydraulic cementsare industrial by-products (e.g. coal combustion, or quality ironproduction), their material properties are a result of the industrialby-product and are not specifically tailored as a quality cementitiousreagent. Accordingly, these materials lack any guarantee of ideal oreven consistent composition and quality, and their suitability ascementitious reagents varies from plant to plant, and over time. Thereis also no control over production location, and the concrete industrylacks control over future availability of these critically importantcementitious materials. It would be much more advantageous if theproduction location could be chosen based on market needs, particularlybecause shipping of cementitious materials is very expensive.

Fly ash is a partially glassy aluminosilicate by-product of coalcombustion. It is frequently used as an admixture in hydraulic cementmixes to improve flowability and create a pozzolanic reaction to improveproperties of concrete including strength, resistance to alkali-silicareaction and others. Unfortunately, only certain coal and combustionprocesses create a consistent supply of fly ash of a quality acceptablefor use in concrete (e.g. ASTM Type C and Type F ash, or CSA Type C, CI,and F ashes). Ash is not produced as an optimal SCM; rather, combustionis optimized for power generation and pollution prevention: there is noguaranteed consistency of by-product ash. Further problems for thefuture of fly ash in concrete include a significant decrease in regionalavailability due to transition from coal energy to natural gas in manymarkets, carbon introduced post-combustion can negatively affect airentrainment in concrete, recovery of ash from impoundments will increasecost, and quality must be verified through testing in each case.

Ground Granulated Blast Furnace Slag (GGBFS) is a glassy CaO—SiO₂by-product of iron production in blast furnaces. Concretes incorporatingGGBFS have many advantageous properties including improved chemicaldurability, whiteness, reduced heat of hydration, mitigation of CO₂footprint, and other beneficial properties. Unfortunately, the supply ofblast furnace slag is quite limited due to the small number of blastfurnaces operating in most markets. As such, GGBFS is in high demand asa quality SCM and prices for this by-product are now similar to theprice of cement itself. Additionally, the limited geographic supplyleads to shortages or at least high shipping costs for many localconcrete markets. Finally, iron production and resulting blast furnaceslag supply are not coupled directly to concrete demand, leaving supplyvolume, local availability, and market price of these importantadmixtures largely up to chance.

Natural pozzolans are siliceous or aluminosiliceous materials that areable to participate in the pozzolanic reaction with Ca(OH)₂. Theseinclude as-mined or calcined volcanic ash, diatomaceous earth, kaoliniteand other clays, MK-750 and other natural minerals and rocks that reactwith lime to produce a hydrated calcium silicate compound. Naturalpozzolans can be very effective SCMs in concrete, however they requiremining of non-renewable resources and pozzolans often requiresignificant shipping distances since deposits are not extremely common.Also, natural materials often require significant processing such ascalcining to enhance reactivity of natural pozzolans.

Fly ash (usually with low CaO content, as in type F), GGBFS, and certainnatural and processed “pozzolans” (e.g. volcanic ashes, zeolites, andMK-750) are also common geopolymer reagents, and the same unfortunatelimitations on supply, geographic availability, price, quality, andconsistency apply for their application in geopolymer binders andcements.

To overcome certain limitations of these existing SCM and geopolymerreagent supplies, several attempts have been made to improve on aspectsof traditional methods. Despite some improvements, these man-madeproducts or compositions still possess numerous deficiencies, forinstance with respect to reactivity and chemistry of reagents for use ingeopolymer chemistry (e.g., optimizing reagents to later produce highcoordination, branched, and three-dimensional alkali/alkaline earthaluminosilicate polymers). They also require expensive lab-gradereagents and cannot simply use globally abundant feedstocks.

Also, previously manufactured glassy cementitious reagents have angularor fibrous particle morphology. Thus, cement pastes made from suchreagents require a lot of water and have relatively poor workability(e.g., with excessive yield stress or higher than optimal plasticviscosity) which is a barrier to use in practical concrete applications.

Combustion ashes and silica fume typically do not have angular particlemorphology. However, these are not available in sufficient quantities,do not have appropriate chemistry, and/or are too expensive to support alarge-scale transition to high SCM blend hydraulic or geopolymercements.

There is thus a need for cementitious reagents that solve existingworkability issues with a similar degree of effectiveness as superplasticizers and water reducers in equivalent Portland cement mixdesigns. There is also a need for a method of reducing CO₂ emissions inproduction of Portland cement, and particularly, a need for anengineered cementitious reagent with low or zero process CO₂ emissionsthat can be used as a supplementary cementitious material in hydrauliccements, and/or as a solid geopolymer reagent.

There is also need for a cementitious reagent that can be producedubiquitously from globally abundant feedstocks, is reactive incementitious systems, and delivers workable low-yield stress cementmixes.

Furthermore, there is a need for production of cementitious reagentswherein the production location could be chosen based on market needs.There is particularly a need for non-angular particle or microspheroidalglassy particles useful in cementitious reagents, geopolymer reagents,supplementary cementitious materials (SCM), cement mixes and concrete.

There is also a need for the economical production of suchmicrospheroidal glassy particles, e.g. by using globally abundantfeedstocks. There is also a need for apparatuses, systems and methodsusing in-flight melting/quenching such wherein solid particles are flownin suspension, melted in suspension, and then quenched in suspension.

The present invention addresses these needs and other needs as it willbe apparent from review of the disclosure and description of thefeatures of the invention hereinafter.

The dominant cement used in concrete today is a hydration-curing calciumsilicate product known as Portland cement. Unfortunately, manufacture ofPortland cement clinker causes CO₂ process emissions (from heatinglimestone) that are globally impactful (about 3-5%, not countingfuel-derived GHG emissions). The process is carried out in a rotary kilnwith raw meal flowing countercurrent to the kiln burner. The process isvery energy intensive, consuming ˜3-5 GJ/ton, of which about 1.5 GJ/tonis spent simply calcining limestone. Of the few viable strategies todecrease environmental impact of cement, geopolymer chemistry provides aglobally viable alternative cement with improved environmental andmaterial performance. The inconsistent supply and limited geographicavailability of traditional geopolymer reagents such as fly ash andslags have limited standardization and adoption of geopolymer concretes.On the other hand, an increasing demand for supplementary cementitiousmaterials (SCM) in hydraulic cements (to enhance material andenvironmental performance) has further squeezed demand for thesematerials.

As mentioned hereinbefore various attempts have been made to manufacturecementitious reagents. However, these methods suffer from crucialdeficiencies that have prevented an economic manufacturing process forglassy cementitious reagents.

For instance, high-temperature refractory-lined furnaces and crucibleshave been used to directly contain glass melts in existing academicresearch on cementitious reagents (a natural extension of traditionalglassmaking techniques). However, solid refractory materials incrucibles and surrounding conventional furnaces require low heating andcooling rates (order of 10-50 C/min) to avoid thermal shock breakage.Conventional melting furnaces have high thermal mass which makesmaintenance difficult and costly as a result of long startup andshutdown cycles. It is preferable to avoid the need for refractoriesthat directly contact the melt, so as to avoid, complexity, wear, andalso considerable start up and shut down times.

Quenching of molten glass for cementitious reagents (blast furnace slag,for example) has previously required water, which is costly, inhibitsheat recovery, could have negative environmental consequences and mayrequire added complication of solid/liquid separation. Melt quenchingmethods were thus either wasteful or slow, diminishing reactivity.Air-quenching methods of cooling melts are either too slow or requirevery specific chemistry to ensure low melt viscosities of about 1 Pa*sor less, which is not feasible for most desired feedstock materials.

Previous glass manufacturing methods have required costly particle sizereduction (milling) of glassy product (typically before and afterthermal processing).

Accordingly, there is still a need for a convenient and economic methodof manufacturing a glassy cementitious reagent from globally abundantfeedstocks.

There is also a need to minimize energy consumption and cope with veryhigh and variable melt viscosity without requiring fluxes.

There is also a need for methods of producing microspheroidal glassyparticles and for apparatuses and systems useful for producing suchmicrospheroidal glassy particles.

The present invention addresses these needs and other needs as it willbe apparent from review of the disclosure and description of thefeatures of the invention hereinafter.

SUMMARY

Embodiments relate to, among other things, an alternative cementmaterial (ACM), which in some embodiments comprises a solidmicrospheroidal glassy particles comprising one or more of the followingproperties: mean roundness (R)>0.8 ; and less than about 40% particleshaving angular morphology (R<0.7).

In some embodiments, the particles comprise a mean roundness (R) of atleast 0.9. In embodiments, less than about 30% particles, or less thanabout 25% particles, or less than about 20% particles, or less thanabout 15% particles, or less than about 10% particles have an angularmorphology (R<0.7).

In some embodiments, the particles comprise the mean oxide Formula 1:(CaO,MgO)a.(Na₂O,K₂O)b.(Al₂O₃,Fe₂O₃)_(c).(SiO₂)d [Formula 1]; wherein ais about 0 to about 4, b is about 0.1 to about 1, c is 1, and d is about1 to about 20.

In some embodiments, the particles further comprise one or more of thefollowing properties: (i) a content of 45%-100%, and preferably 90-100%,X-ray amorphous solid; and (ii) molar composition ratios of(Ca,Mg)0-12.(Na,K)0.05-1.(Al, Fe3+)1.Si1-20.

According to another aspect, some embodiments relate to a cementitiousreagent comprising a mixture of microspheroidal glassy particles asdefined herein.

According to another particular aspect, some embodiments the inventionrelate to a cementitious reagent comprising a mixture of microspheroidalglassy particles, these particles comprising one or more of thefollowing properties: (i) mean roundness (R)>0.8; (ii) less than about20% particles having angular morphology (R<0.7); (iii) the oxide Formula1 as defined hereinbefore; (iv) a content of 45%-100%, and preferably90-100%, X-ray amorphous solid; and (v) a molar composition ratios of(Ca,Mg)₀₋₁₂.(Na,K)_(0.05-1).(Al, Fe³⁺)₁.Si₁₋₂₀; and (vi) a low calciumcontent of about <10wt % CaO, or an intermediate calcium content ofabout 10 to about 20% wt % CaO, or a high calcium content of >30 wt %CaO.

In some embodiments, the cementitious reagent is in the form of anon-crystalline solid. In some embodiments, the cementitious reagent isin the form of a powder. In some embodiments, the particle sizedistribution with D[3,2] (i.e., surface area mean, or Sauter MeanDiameter) of about 20 μm or less, more preferably 10 μm or less, or mostpreferably 5 μm or less. In one embodiment, the mixture ofmicrospheroidal glassy particles of the cementitious reagent comprisesthe oxide Formula 1 as defined hereinabove. In some embodiments, thecementitious reagent comprises less than about 10 wt. % CaO. In someembodiments, the cementitious reagent comprises more than about 30 wt. %CaO. In some embodiments the cementitious reagent is about 40-100% andpreferably about 80% X-ray amorphous, 90% X-ray amorphous, and up toabout 100% X-ray amorphous, and in some embodiments, is 100%non-crystalline.

According to some embodiments, a geopolymer binder comprises acementitious reagent as defined herein. According to another particularaspect, some embodiments of the invention relate to a supplementarycementitious material (SCM) comprising a cementitious reagent as definedherein, for instance a SCM comprising at least 20 wt. % of thecementitious reagent.

According to another particular aspect, some embodiments relate to asolid concrete comprising a cementitious reagent as defined herein.

According to another particular aspect, some embodiments relate to theuse of microspheroidal glassy particles as defined herein, and to theuse of a cementitious reagent as defined, to manufacture a geopolymerbinder or cement, a hydraulic cement, a supplementary cementitiousmaterial (SCM) and/or solid concrete.

According to another particular aspect some embodiments relate to amethod for producing a cementitious reagent from aluminosilicatematerials, comprising the steps of: (i) providing a solidaluminosilicate material; (ii) in-flight melting/quenching said solidaluminosilicate material to melt said material into a liquid andthereafter to quench said liquid to obtain a molten/quenched powdercomprising solid microspheroidal glassy particles; thereby obtaining acementitious reagent with said powder of microspheroidal glassyparticles.

In some embodiments, the method further comprises step (iii) of grindingsaid powder of microspheroidal glassy particles into a finer powder. Inone embodiment, the powder comprises particle size distribution withD[3,2] of about 20 μm or less, more preferably 10 μm or less, or mostpreferably 5 μm or less.

In some embodiments, the cementitious reagent obtained by the methodcomprises one or more of the following properties: is reactive incementitious systems and/or in geopolymeric systems; delivers workablelow yield stress geopolymer cement mixes below 25 Pa when a cement pastehas an oxide mole ratio of H₂O/(Na₂O,K₂O)<20]; requires water content incement paste such that the oxide mole ratio H₂O(Na₂O,K₂O)<20; anddelivers a cement paste with higher workability than an equivalent pastewith substantially angular morphology, given the same water content.

In some embodiments, the method further comprises the step of adjustingcomposition of a non-ideal solid aluminosilicate material to a desiredcontent of the elements Ca, Na, K, Al, Fe, and Si. In one embodiment theadjusting comprises blending a non-ideal aluminosilicate material with acomposition adjustment material in order to reach desired ratio(s) withrespect to one or several of the elements Ca, Na, K, Al, Fe, and Si.

In some embodiments, the method further comprises the step of sortingthe solid aluminosilicate material to obtain a powder of aluminosilicateparticles of a desired size. In some embodiments, the method furthercomprises the step of discarding undesirable waste material from saidsolid aluminosilicate material.

In some embodiments, the in-flight melting comprises heating at atemperature above a liquid phase temperature to obtain a liquid. In someembodiments, the temperature is between about 1000-1600° C., or betweenabout 1300-1550° C.

In some embodiments, the method further comprises the step of adding afluxing material to the solid aluminosilicate material to lower itsmelting point and/or to induce greater enthalpy, volume, ordepolymerization of the liquid. In some embodiments, the fluxingmaterial is mixed with the solid aluminosilicate material prior to, orduring the melting.

In some embodiments, the in-flight melting/quenching comprises reducingtemperature of the liquid below temperature of glass transition toachieve a solid. In some embodiments, the in-flight melting/quenchingcomprises reducing temperature of the liquid below about 500° C., orpreferably below about 200° C. or lower. In some embodiments, reducingtemperature of the liquid comprises quenching at a rate of about 10²Ks⁻¹ to about 10⁶ Ks⁻¹, preferably at a rate of >10^(3.5) Ks⁻¹. In someembodiments, quenching comprises a stream of cool air, steam, or water.In one embodiment, the method further comprises separating quenchedsolid particles from hot gases in a cyclone separator.

In some embodiments, the method for producing a cementitious reagentfrom aluminosilicate materials further comprises reducing particle sizeof the powder of solid microspheroidal glassy particles. In someembodiments reducing particle size comprises crushing and/or pulverizingthe powder in a ball mill, a roller mill, a vertical roller mill or thelike.

According to another aspect, some embodiments relate to an apparatus forproducing microspheroidal glassy particles, the apparatus comprising aburner, a melting chamber and a quenching chamber. The melting chamberand the quenching chamber may be completely separate or may be first andsecond sections of the same chamber, respectively.

The apparatus may be configured such that solid particles are flown insuspension, melted in suspension, and then quenched in suspension in theapparatus.

In some embodiments, the burner provides a flame heating solid particlesin suspension to a heating temperature sufficient to substantially meltsaid solid particles into a liquid. In some embodiments, the burnercomprises a flame that is fueled with a gas that entrainsaluminosilicate feedstock particles towards the melt/quench chamber. Thegas may comprise an oxidant gas and a combustible fuel. In someembodiments the burner comprises at least one of a plasma torch, anoxy-fuel burner, an air-fuel burner, a biomass burner, and a solarconcentrating furnace.

In some embodiments, the quenching chamber of the apparatus comprises acooling system for providing cool air inside the quenching chamber, thecool air quenching molten particles to solid microspheroidal glassyparticles. In some embodiments, the cooling system comprises a liquidcooling loop positioned around the quenching chamber.

In some embodiments, the apparatus further comprises a cyclone separatorto collect microspheroidal glassy particles. According to someembodiments, a method for producing a cementitious reagent fromaluminosilicate materials comprises the steps of: (i) providing a solidaluminosilicate material; (ii) in-flight melting/quenching said solidaluminosilicate material to melt said material into a liquid andthereafter to quench said liquid to obtain a molten/quenched powdercomprising solid microspheroidal glassy particles; thereby obtaining acementitious reagent with said powder of microspheroidal glassyparticles.

According to some embodiments, a method for producing microspheroidalglassy particles comprises the steps of: providing an in-flightmelting/quenching apparatus comprising a burner, a melting chamber and aquenching chamber; providing solid particles; flowing said solidparticles in suspension in a gas to be burned by said burner; heatingsaid solid particles into said melting chamber to a heating temperatureabove liquid phase to obtain liquid particles in suspension; andquenching said liquid particles in suspension to a cooling temperaturebelow liquid phase to obtain a powder comprising solid microspheroidalglassy particles.

In some embodiments of these methods, the solid particles comprisealuminosilicate materials. In some embodiments of these methods, theheating temperature is between about 1000-1600° C., or between about1300-1550° C. In some embodiments of these methods, the cooling (quench)temperature is below about 500° C., or below about 200° C.

In some embodiments of these methods, the quenching comprises providingcool air inside the quenching chamber. In some embodiments, thesemethods further comprise collecting the powder with a cyclone separator.

Additional aspects of some embodiments of the invention relate to theuse of an apparatus as defined herein, particularly an apparatuscomprising at least one of a plasma torch, an oxy-fuel burner, anair-fuel burner, a biomass burner, and a solar concentrating furnace,for producing microspheroidal glassy particles using in-flightmelting/quenching.

Additional aspects of some embodiments of the invention relate to theuse of an apparatus as defined herein, particularly an apparatuscomprising at least one of a plasma torch, an oxy-fuel burner, anair-fuel burner, a biomass burner, and a solar concentrating furnace,for producing a cementitious reagent from aluminosilicate materialsusing in-flight melting/quenching.

Additional aspects, advantages and features of the present inventionwill become more apparent upon reading of the following non-restrictivedescription of preferred embodiments which are exemplary and should notbe interpreted as limiting the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

A better understanding of the features, advantages and principles of thepresent disclosure will be obtained by reference to the followingdetailed description that sets forth illustrative embodiments, and theaccompanying drawings of which:

FIG. 1 is a flow diagram showing production of a cementitious reagentstarting from a solid aluminosilicate material, in accordance with someembodiments;

FIG. 2 is a set of four ternary CaO, MgO—SiO₂—(Na₂O,K₂O)—(Al₂O₃, Fe₂O₃)composition diagrams, in accordance with some embodiments;

FIG. 3 is a three-dimensional quaternary diagram in (CaO, MgO)—(Al₂O₃,Fe₂O₃) —(Na₂O, K₂O)—(SiO₂) space using the same material compositionaldata plotted in FIG. 2 , in accordance with some embodiments;

FIG. 4 is a particle size distribution graph comparing angular andspheroidal particle size distributions for commercially availablenatural volcanic glass powder (angular morphology) and particlesproduced in accordance with Example 1 (spheroidal morphology).Percentage of particles by volume below a given diameter (y axis) isprovided as a function of particle diameter in micrometers (x axis).Electron microphotographs demonstrate particle morphology of thesamples.

FIG. 5 is a graph providing a comparison of particle roundness (R)distributions of various powders, in accordance with some embodiments;(211-218, 519, 520, as defined hereinafter) before processing (501) andafter (502) processing in accordance with Examples 1-8, in accordancewith some embodiments. Image analysis was used to determine R valuesfrom microphotographs of the same powders shown in FIG. 6 and FIG. 7following the method of Takashimizu & Liyoshi (Takashimizu, Y., Iiyoshi,M. (2016). New parameter of roundness R: circularity corrected by aspectratio. Progress in Earth and Planetary Sciences 3, 2.https://doi.org/10.1186/s40645-015-0078-x). Also see Table 17 for moreprecise data. For convenience, two Type F fly ash samples are alsoincluded; 519 (B-FA) a beneficiated fly ash sold commercially, and 520(L FA) an unbeneficiated fly ash direct from a coal power plant.

FIG.6 is a panel showing a collection of electron microphotograph pairscomparing unprocessed particles (501) and processed particles (502) fromvarious materials (211-218 as defined hereinafter) as described inExample 1 through Example 8. Field of view width for individual panelsis 140 μm.

FIG. 7 is a panel showing pictures of two Type F fly ashes, one directlyfrom a coal power plant in Nova Scotia (L-FA; 520) and anothercommercially available fly ash that has been beneficiated to removeactivated carbon and other contaminants (B-FA; 519). Field of view widthfor individual panels is 140 μm.

FIG. 8 is a schematic process flow diagram of a system to produce aglassy microspheroidal cementitious reagent, in accordance with oneembodiment of the invention.

FIGS. 9A and 9B are a photograph and a corresponding illustration,respectively of a burner flame (bottom) entering a melt/quench chamber(top) with entrained aluminosilicate feedstock particles, in accordancewith one embodiment of the invention.

FIG. 10 is a schematic drawing of an improved in-flight meltingapparatus that includes heat recovery loops for minimizing energy inputand CO₂ emissions, in accordance with one embodiment of the invention.

FIG. 11 illustrates the complete set of ternary representations of aNovel Composition closed to Si, Al, Fe, Ca+Mg and Na+K; in accordancewith some embodiments;

FIG. 12 illustrates ternary diagrams for a Novel Composition from the Siperspective; in accordance with some embodiments;

FIG. 13 illustrates ternary diagrams for a Novel Composition from the Alperspective; in accordance with some embodiments;

FIG. 14 illustrates ternary diagrams for a Novel Composition from the Feperspective; in accordance with some embodiments;

FIG. 15 illustrates ternary diagrams for a Novel Composition from theCa+Mg perspective; in accordance with some embodiments;

FIG. 16 is a schematic flow diagram describing the process of making analternative cement concrete using a relatively small decentralizedin-flight minikiln, in accordance with some embodiments;

FIG. 17 is a schematic diagram showing conventional cement and aggregatedistribution in a modern centralized Portland cement kiln supply chain,in accordance with some embodiments;

FIG. 18 is a schematic diagram showing the transportation advantages ofcollocating alternative cement material (ACM) minikilns at aggregatequarries in a novel decentralized method, in accordance with someembodiments;

FIG. 19 is a schematic diagram showing the transportation advantages ofcollocating alternative cement material (ACM) minikilns at concretebatch plants in a novel decentralized method, in accordance with someembodiments; and

FIG. 20 is a schematic diagram showing the transportation advantages oflocating alternative cement material (ACM) minikilns in a noveldecentralized manner at independent sites in the vicinity of aggregatequarries and concrete batch plants, in accordance with some embodiments.

Further details of the invention and its advantages will be apparentfrom the detailed description included below.

DETAILED DESCRIPTION

The following detailed description and provides a better understandingof the features and advantages of the inventions described in thepresent disclosure in accordance with the embodiments disclosed herein.Although the detailed description includes many specific embodiments,these are provided by way of example only and should not be construed aslimiting the scope of the inventions disclosed herein.

In the following description of the embodiments, references to theaccompanying drawings are by way of illustration of an example by whichembodiments of the invention may be practiced. It will be understoodthat other embodiments may be made without departing from the scope ofthe invention disclosed.

Microspheroidal Glassy Particles

Some embodiments relate to the production and uses of solidmicrospheroidal glassy particles. As explained with more detailshereinafter, a related aspect concerns a cementitious reagent comprisinga mixture or plurality of such microspheroidal glassy particles.

In accordance with the invention, the solid microspheroidal glassyparticles are appreciably round particles of high sphericity.

As used herein, the term “roundness” and corresponding unit “R” refersto roundness as defined by Takashimizu & ILyoshi (2016). The valuesrequired to calculate R can be determined by performing image analysison appropriate photomicrographs of powders. R (roundness) provides aconvenient quantitative measure of roundness that is highly correlatedwith Krumbein's “roundness” (Krumbein, W. C. (1941) Measurement andgeological significance of shape and roundness of sedimentary particles.Journal of Sedimentary Petrology 11:64-72.https://doi.org/10.1306/D42690F3-2B26-11D7-8648000102C1865D.)

In some embodiments, the microspheroidal glassy particles have meanroundness (R) of at least 0.9 (Standard deviation <0.15).

In some embodiments, the microspheroidal glassy particles have bulkroundness (R) of at least 0.8 (Standard deviation <0.15).

In some embodiments, the microspheroidal glassy particles have bulkroundness (R) of at least 0.7, or 0.6, or 0.5 (Standard deviation<0.15).

In some embodiments, a mixture of microspheroidal glassy particlescomprises less than about 50% particles, or less than about 40%particles, or less than about 30% particles, or less than about 25%particles, or less than about 20% particles, or less than about 15%particles, or less than about 10% particles having angular morphology(e.g., R<0.7) .

In some embodiments, a mixture or plurality of microspheroidal glassyparticles is provided in a powder form comprising a particle sizedistribution with D[3,2] of about 20 μm or less, more preferably about10 μm or less, or most preferably about 5 μm or less.

In some embodiments, microspheroidal glassy particles are anon-crystalline solid.

In some embodiments, the microspheroidal glassy particles comprise theoxide Formula 1: (CaO,MgO)a.(Na₂O,K₂O)b.(Al₂O3,Fe₂O₃)c.(SiO₂)d [Formula1] wherein a is about 0 to about 4, b is about 0.1 to about 1, c is 1,and d is about 1 to about 20.

In some embodiments, the microspheroidal glassy particles comprise oneor more of the following properties: (i) a content of 45%-100%, andpreferably 90-100%, X-ray amorphous solid; and (ii) molar compositionratios of (Ca,Mg)₀₋₁₂*(Na,K)_(0.05-1).(Al, Fe³⁺)₁.Si₁₋₂₀.

In some embodiments, the microspheroidal glassy particles are 40-100%X-ray amorphous, more preferably about 80 to about 100% X-ray amorphous,and in some embodiments is 100% non-crystalline.

In some embodiments, the particles comprise less than about 10 wt. %CaO.

In some embodiments, the particles comprise more than about 30 wt. %CaO.

In some embodiments, the particles comprise a high-calcium content witha molar composition of Si/(Fe³⁺,Al) between 1-20, and CaO content ofabout 10- about 50 wt. %, preferably about 20-45 wt. %.

In some embodiments, the particles comprise an intermediate-calciumcontent with a molar composition of Si/(Fe³⁺,Al) between 1-20, and CaOcontent of about 10- about 20 wt. %.

As described hereinafter, the microspheroidal glassy particles mayadvantageously be produced from globally abundant inorganic feedstockssuch as aluminosilicate material. As used herein, the term“aluminosilicate material” refers to a material comprising aluminum oraluminum and iron, and silicon dioxide selected from natural rocks andminerals, dredged materials, mining waste comprising rocks and minerals,waste glass, aluminosilicate-bearing contaminated materials andaluminosiliceous industrial by-products. An aluminosilicate materialaccording to the present invention is preferably in the form of acrystalline solid (e.g. at least 50 wt. %, or at least 60 wt. %, or atleast 70 wt. %, or at least 80 wt. %, or at least 90 wt. %, or 100 wt. %crystalline solid). In some embodiments, the aluminosilicate materialcomprises at least 2 wt. % (Na₂O,K₂O), or at least 3 wt. % (Na₂O,K₂O),or at least 4 wt. % (Na₂O,K₂O), or at least 5 wt. % (Na₂O,K₂O), at least6 wt. % (Na₂O,K₂O), or at least 7 wt. % (Na₂O,K₂O), or at least 8 wt. %(Na₂O.K₂O), or at least 10 wt. % (Na₂O,K₂O), or at least 12 wt. %(Na₂O,K₂O), or at least 15 wt. % (Na₂O,K₂O), or at least 20 wt. %(Na₂O,K₂O). In some instances, the inorganic feedstocks areheterogeneous, and the glassy particles produced are more homogeneousthan the feedstock, as shown during partial homogenization duringmelting. That is, more than 10% of the particles produced fall within anew intermediate formulation range.

In some embodiments the aluminosilicate material is selected fromdredged sediments, demolished concrete, mine wastes, glacial clay,glacial deposits, fluvial deposits, rocks and mineral mixtures, forinstance rocks and mineral mixtures composed of some or all the elementsCa, Mg, Na, K, Fe, Al and Si. These aluminosilicate materials are widelyabundant in many different geographic regions.

As described hereinafter, the elemental composition of the feedstock maybe analyzed and optimized for desired uses. The feedstock may beanalyzed by quantitative or semi-quantitative methods such as XRF, XRD,LIBS, EDS, wet chemical analysis, and various other existing methods todetermine the feedstock elemental composition.

As described hereinafter, the microspheroidal glassy particles may beproduced using a process or method for in-flight thermochemicalprocessing such as in-flight melting/quenching and/or suspensionmelting, for melting into a liquid the starting inorganic materials andthereafter quenching the liquid into solid particles. As used herein,the term “in-flight melting/quenching” or “suspension melting” refers toa process wherein solid particles are flown in suspension, melted insuspension, and then quenched in suspension to obtain a powder.

In some embodiments, the term “microspheroidal glassy particles”encompasses particles as defined hereinabove that are found in thepowder resulting directly from an in-flight melting/quenching process.In embodiments, the term “microspheroidal glassy particles” refers toparticles obtained after grinding or milling (e.g. jaw crusher, animpact mill, etc.) of the powder obtained after the in-flightmelting/quenching process.

As described hereinafter, the microspheroidal glassy particles find manyuses including, but not limited to, as or in the preparation ofcementitious reagents, as or in the preparation of geopolymer binders orcements, as or in the preparation of hydraulic cements, as or in thepreparation of supplementary cementitious materials (SCMs), and in themaking of solid concrete.

One additional use may be as a fertilizer or soil amendment, e.g. as asubstitute to “rock dust”.

Cementitious Material

Some embodiments described herein relate to cementitious reagent powderscomprising microspheroidal glassy particles as defined herein.

Some embodiments also relate to geopolymer binders or cements, hydrauliccements, supplementary cementitious materials (SCMs), hydraulic concretemixtures, and solid concrete powders comprising microspheroidal glassyparticles as defined herein.

Particle morphology has a considerable impact on physical properties andhandling of cement slurries. Accordingly, the high-roundness morphologyof the particles according to the present invention advantageouslyprovides increased workability, fluidity, and/or decreased water demandfor geopolymer cement mixes. In particular, having high degrees ofroundness reduces yield stress and viscosity of cement mixes by reducinginterparticle friction. Additionally, spheroidal morphology decreaseswater demand by improving packing for a given particle sizedistribution.

As illustrated in FIGS. 2 and 3 , the composition of cementitiousreagents in accordance with embodiments of the invention is differentfrom existing cementitious materials. Indeed, considering combinationsof ternary compositions of element groups (CaO, MgO), (Al₂O₃, Fe₂O₃),(Na₂O, K₂O), and (SiO₂), embodiments of a cementitious reagent 201occupies a position in these figures that is different and distinct fromfly ash (C and F) 202, ground-granulated blast-furnace slag (GGBS orGGBFS) 203, metakaolin 204, and Portland cement 205. Examples ofspecific feedstock compositions are shown in FIG. 2 : volcanic pumice211 (Example 1), basalt 212 (Example 2), a second basalt 213 (Example3), coal tailings samples 214 (Example 4), dredged sediment 215 (Example5), copper porphyry flotation tailings 216 (Example 6), demolishedconcrete 217 (Example 7), dioritic aggregate crusher dust 218 (Example8).

Advantageously, the cementitious reagent is formulated from globallyabundant rock, minerals and compounds of suitable composition. In thisway, the abundant feedstock may not need to be shipped very far to aprocessing facility, or a cement plant. In some instances, a cementplant is built at the feedstock location.

In some embodiments, a cementitious reagent comprises a mixture ofmicrospheroidal glassy particles as defined herein and further comprisesone or more of the following properties: (i) is in the form of anon-crystalline solid; (ii) is in the form of a powder; (iii) comprisesparticle size distribution with D[3,2] of about 20 μm or less, morepreferably 10 μm or less, or most preferably 5 μm or less; (iv)comprises the oxide Formula 1, as defined hereinbefore; (v) a content of45%-100%, and preferably 90-100%, X-ray amorphous solid; (vi) a molarcomposition ratios of (Ca,Mg)₀₋₁₂.(Na,K)_(0.05-1).(Al, Fe³⁺)₁.Si₁₋₂₀;(vii) comprises less than about 10 wt. % CaO; (viii) comprises more thanabout 30 wt. % CaO; (ix) comprises a molar composition of Si/(Fe³⁺,Al)between 1-20, and CaO content of about 10- about 50 wt. %, preferablyabout 20-45 wt. %; (x) comprises a molar composition of Si/(Fe³⁺,Al)between 1-20, and CaO content of about 10- about 20 wt. %; (xi) is40-100% X-ray amorphous, more preferably above 80%, above 90%, and insome cases, up to about 100% X-ray amorphous, and in some cases, is 100%non-crystalline; (xii) comprises a particle size distribution withD[3,2] of about 20 μmor less, more preferably about 10 μmor less, ormost preferably about 5 μm or less.

In some cases, the CaO content is lower than about 30 wt. % in order toreduce the CO2 impact of cement by avoiding a need for decomposition ofcarbonate-sourced calcium.

In some embodiments, the cementitious reagent comprises less than about10 wt. % CaO. In some embodiments, the cementitious reagent comprisesmore than about 30 wt. % CaO. In some instances, the composition ofcementitious reagent with respect to molar ratio of (Na, K), and Ca maybe varied to obtain certain advantages depending on the binderrequirements. For example, a cementitious reagent with less than about10 wt. % CaO is suitable for use in heat-cured geopolymer and as a flyash substitute. In the alternative, a cementitious reagent with greaterthan about 30 wt. % CaO has hydraulic properties and may be added togeopolymer resin to allow ambient-temperature curing of geopolymercement, and directly replaces blast furnace slag in blended Portlandcement.

In some embodiments, the cementitious reagent is a low-calciumcontaining cementitious reagent with a molar composition of Si/(Fe³⁺,Al)between 1-20, and with a CaO content of about 10 wt. % or less.Preferably such cementitious reagent is 40-100% X-ray amorphous, morepreferably about 80% to about 100% X-ray amorphous, and in someembodiments 100% non-crystalline. Such low-calcium containingcementitious reagent may find numerous commercial applications, forinstance, as a pozzolanic admixture in hydraulic cement, and/or as areagent in geopolymer binders and cements.

In some embodiments, the cementitious reagent is a high-calciumcontaining cementitious reagent with a molar composition of Si/(Fe³⁺,Al)between 1-20, and CaO content of about 10- about 50 wt. %, preferablyabout 20-45 wt. %. Preferably such cementitious reagent is 40-100% X-rayamorphous, more preferably about 80- about 100% X-ray amorphous, evenmore preferably 100% non-crystalline. Such a high-calcium containingcementitious reagent may find numerous commercial applications, forinstance as a hydraulic admixture in blended hydraulic cement, and/or asa reagent in geopolymer binders and cements.

In some embodiments, the cementitious reagent is an intermediate-calciumcontaining cementitious reagent with a molar composition of Si/(Fe³⁺,Al)between 1-20, and CaO content of about 10- about 20 wt. %. Preferablysuch cementitious reagent is about 40-100% and preferably about 80% toabout 100% X-ray amorphous, and even more preferably 100%non-crystalline. Such an intermediate-calcium containing cementitiousreagent may find numerous commercial applications, for instance as acementitious reagent with desirable intermediate hydraulic andpozzolanic properties, particularly in ambient-curing geopolymerapplications.

In some embodiments, the Na,K content in the cementitious reagent isoptimized. This may be advantageous for SCM applications where free limein hydraulic cement will exchange with soluble alkalis and coordinatewith sialate molecules derived from cementitious reagent to create someextent of relatively stable alkali aluminosilicate polymerization thatgreatly improves chemical properties of traditional hydraulic cements.In embodiments, the Na,K content is optimized due to the fact thatgeopolymer reagents with significant Na,K contents require less solublesilicate hardener than would otherwise be necessary, thus decreasing thesoluble silicate requirement (and cost) of a geopolymer mix design.

Methods of Preparation

Microspheroidal glassy particles as defined herein, as well ascompositions comprising same such as cementitious reagents, geopolymerbinders or cements, hydraulic cements, supplementary cementitiousmaterials (SCMs), and concrete can be prepared using any suitable methodor process.

FIG. 1 shows exemplary steps necessary to produce cementitious reagentfrom aluminosilicate materials in accordance with some embodiments.Briefly, a finely divided aluminosilicate material powder 101 isselected and its chemical composition is analyzed 102 and evaluated. Thefeedstock may be analyzed by any suitable quantitative orsemi-quantitative methods such as XRF, XRD, LIBS, EDS, wet chemicalanalysis, and various other existing methods to determine the feedstockelemental composition.

If the selected composition is not acceptable, the material isoptionally amended, blended (e.g. in a vessel prior to thermochemicalprocessing), for example, through addition of a composition adjustmentmaterial 104 (see hereinafter) or sorted 103 and any undesirable wastematerial may be discarded.

The resulting solid aluminosilicate material comprising a powder ofdesirable composition is next heated 106 and individual particles orparticle agglomerates are melted into a liquid in suspension. Next theliquid particles in suspension are quenched 107 to obtain a powdercomprising solid microspheroidal glassy particles. Next, the powder isoptionally crushed and/or pulverized (partially or entirely) 108 if itis desired to reduce particle size and/or to optimize reactivity andobtain the cementitious reagent 109.

Regarding the addition of a composition adjustment material 104, as usedherein the term “composition adjustment material” refers to any solid orliquid material with a composition suitable for preferentially alteringthe bulk or surface composition of aluminosilicate material with respectto one or several of the elements Ca, Na, K, Al, Fe, and Si.

Composition adjustment materials that introduce calcium (Ca) may becomprised of calcium salts including CaCO₃, Ca(OH)₂, CaO, CaC₁, CaF₂,calcium silicate minerals and compounds, calcium aluminum silicateminerals and compounds, waste Portland cement products, waste hydrauliccement products, wollastonite, gehlenite, and other melilite groupmineral compositions.

Composition adjustment materials that introduce aluminum (Al) may becomprised of aluminous rocks, minerals, soils, sediments, by-products,and compounds including one or more of kaolinite, halloysite and otheraluminum-rich/alkali-poor clay minerals, Al₂SiO₅ polymorphs, chloritoid,staurolite, garnet, corundum, mullite, gehlenite, diaspore, boehmite,gibbsite, and nepheline and other feldspathoids. Other materials thatmay be used include aluminum metal, bauxite, alumina, red mud (aluminarefinery residues).

Composition adjustment materials that introduce iron (Fe) may becomprised of iron-rich rocks, minerals, soils, sediments, by-products,and compounds such as olivine, chlorite minerals (chamosite,clinochlore, etc.), pyroxenes, amphiboles, goethite, hematite,magnetite, ferrihydrite, lepidicrocite and other iron oxy-hydroxidecompositions, iron-rich clay and phyllosilicate minerals, iron oretailings, and elemental iron.

Regarding the heating 106, the heating is carried out to reach a heatingtemperature above a liquid phase temperature to obtain a liquid, forinstance at about 1000-1600° C., or about 1300-1550° C. Any suitablemethod or apparatus may be used for the heating and for obtaining theliquid including, but not limited to, in-flight melting (i.e. suspensionmelting). This may be achieved by using an in-flight melting apparatusequipped with, for instance, one or more plasma torches, oxy-fuelburners, air-fuel burners, biomass burners, a solar concentratingfurnace. Typically, a furnace temperature of 1000-1600° C. is needed,and most typically 1300-1550° C., to rapidly obtain the desired liquidphase particles in suspension. In embodiments, the device is selectedsuch that melting is as fast as possible. An example of a suitablein-flight melting apparatus and method is described hereinafter.

Regarding the quenching 107, in some embodiments the quenching stepcomprises reducing temperature of the liquid below the glass transition,for instance at about 500° C. or lower, or preferably below about 200°C. or lower. In embodiments, the quenching is done rapidly, i.e. thetemperature is reduced at a rate of about 10² Ks⁻¹-10⁶ Ks⁻¹ (preferablyat a rate of >10^(3.5) Ks⁻¹). Any suitable method may be used for thequenching including, but not limited to, contacting the molten materialwith a sufficient stream of adequately cool air, with steam, or withwater to produce a non-crystalline solid.

If desired, a fluxing material may be added to the solid aluminosilicatematerial in order to lower its melting point and/or to inducedepolymerization of the liquid. The fluxing material may be mixed withthe solid aluminosilicate material prior to heating/melting or duringthe heating/melting. Common fluxing materials that may inducedepolymerization in melts, and/or lower melting temperature includesCaF₂, CaCO₃, waste glass, glass cullet, glass frit, alkali-bearingminerals (e.g. feldspars, zeolites, clays, and feldspathoid minerals),borate salts, halogen compounds (fluoride and chloride bearing salts)and calcium salts.

Regarding the optionally crushing and/or pulverization step 108, thismay be carried out using any suitable method or apparatus including, butnot limited to, a ball mill, a roller mill and a vertical roller mill.Preferably the particle size is reduced to obtain a fine powder usefulin cementitious applications. Obtaining a finer powder may be useful forincreasing surface area and providing for faster reaction rates, asdescribed for instance in Example 9. Those skilled in the art will beable to determine the size of the particles desired for a particularneed, taking into consideration an economic trade-off between loss ofspherical morphology/workability, cost of grinding, and finalperformance requirements. In embodiments, the powder comprises aparticle size distribution with D[3,2] of approximately 10 μm or less,or preferably 5 μm or less. Such a particle size is generally desirableto ensure sufficient reactivity and consistent material properties.

Uses of Aluminosilicate Materials

As described herein, some embodiments concern the use of aluminosilicatematerials to produce solid microspheroidal glassy particles andnon-crystalline cementitious reagents as defined herein.

Another aspect is the use of in-flight thermochemical processing ofaluminosilicate materials to produce solid microspheroidal glassyparticles and/or of solid cementitious reagents. The glassy particlesand solid cementitious reagents described herein may advantageously beused as an alternative supplementary cementitious material (SCM) inblended hydraulic cement and/or as a geopolymer solid reagent ingeopolymer binders (thus eliminating the need for some or all of MK-750,fly ash, GGBFS, and other common solid reagents).

Another related aspect is the use of an aluminosilicate material toproduce at least one of a supplementary cementitious material (SCM) anda geopolymer reagent comprising solid microspheroidal glassy particlesand/or a non-crystalline cementitious reagent as defined herein.

Uses of the Microspheroidal Glassy Particles and Cementitious Reagent

One aspect of described embodiments concerns the broad relevance of thesolid microspheroidal glassy particles and cementitious reagentdescribed herein. Appropriate compositions of engineered cementitiousreagent may be used interchangeably in significant proportion in bothgeopolymer cements and hydraulic cements (i.e. cements that react withwater).

Accordingly, some embodiments encompass geopolymer cements and hydrauliccements comprising at least 5 wt. %, or at least 10 wt. %, or at least15 wt. %, or at least 20 wt. %, or at least 25 wt. %, or at least 30 wt.%, or at least 40 wt. %, or at least 50 wt. %, or at least 60 wt. %, orat least 70 wt. %, or at least 80 wt. %, or at least 90 wt. %, or more,of solid microspheroidal glassy particles and/or cementitious reagent asdefined herein.

In accordance with some aspects, some embodiments described hereinrelate to a supplementary cementitious material (SCM) comprising acementitious reagent as defined herein. In some embodiments, the SCMcomprises about 5 wt. % to about 50 wt. % (preferably at least 20 wt. %)of solid microspheroidal glassy particles and/or of the cementitiousreagent as defined herein.

In accordance with another aspect, some embodiments described hereinrelate to a supplementary cementitious material (SCM) comprising one ormore of the following properties: it comprises less than about 35 wt. %CaO, with appreciable content of Na+K (e.g. at least 2 wt. %, preferablyat least 5 wt. %) and Al content (e.g. at least 5 wt. %) and is in theform of a non-crystalline solid.

In accordance with another aspect, some embodiments relate to a solidconcrete, comprising solid microspheroidal glassy particles and/or acementitious reagent as defined as defined herein, i.e. comprising about5 wt. % to about 50 wt. % (preferably at least 10 wt. %, or at least 20wt. %, least 30 wt. %, or least 40 wt. %) of solid microspheroidalglassy particles and/or of the cementitious reagent as defined herein.

In accordance with another aspect, some embodiments relate to solidgeopolymer concrete comprising about 5 wt. % to about 50 wt. %(preferably at least 10 wt. %, or at least 20 wt. %, least 30 wt. %, orleast 40 wt. %) of solid microspheroidal glassy particles and/or of thecementitious reagent as defined herein.

Those skilled in the art can appreciate that embodiments of the presentinvention advantageously provide means to produce versatile low-CO₂cementitious reagents from abundant, cheap, natural materials. Anothersignificant advantage is the creation of a single reagent that meetstoday's specification standards for alternative SCMs, while also meetingthe needs of the growing geopolymer market. Further, the cementitiousreagents are formed from diverse, heterogeneous feedstocks, and throughthe described processes, result in a reagent material that is morehomogeneous and suitable as a cementitious reagent.

As can be appreciated, one advantage of the systems and methodsdescribed herein is to provide control over the final composition of thecementitious reagent, thereby producing a reagent with predictablecomposition, which is very important to the industry. Such tailoredcomposition is not available in other existing cementitious reagents,because they are typically obtained from industrial by-products. Inaccordance with embodiments described herein, it is possible to modifylocal feedstocks where necessary to standardize performance for givenapplications. For example, in SCM for Portland cement it may bedesirable to limit alkali content, but in geopolymer systems it may bedesirable to have high alkali content and lessen the need for alkalisilicate hardener. In both scenarios, composition modifications may bedesirable to limit compositional variability of the feedstock.

Another notable concern for the chemistry of geopolymer reagents islabile calcium content. Adjustment of calcium content and phasecontaining the calcium are both important variables for adjusting rateof strength gain under different temperature conditions and finalmaterial properties of geopolymer cement. The methods described hereinmake it possible to engineer certain advantageous compositions ofmicrospheroidal cementitious reagents which is not currently possiblefor by-product-based cementitious reagents.

In-Flight Melting Apparatus, Method and System

Embodiments also relate to an apparatus, a system, and related methodsfor the thermochemical production of glassy cementitious reagents withspheroidal morphology.

According to some embodiments, an apparatus is configured for in-flightmelting/quenching. According to some embodiments, such as thoseillustrated in FIGS. 9A and 9B, the apparatus 900 comprises: a burner809; and a melting chamber combined with a quenching chamber 902. Insome embodiments the melting chamber and the quenching chamber may befirst and sections of the same chamber 902, respectively. In someembodiments, the melting chamber and the quenching chamber are separateconsecutive chambers.

As illustrated, the apparatus 900 is configured for in-flightmelting/quenching. Aluminosilicate feedstock particles 903 enters themelt/quench chamber (top; 902) suspended in a flame 901 combusting anoxidant gas 807 with a combustible fuel 808. The aluminosilicatefeedstock particles 903 are entrained by a venturi eductor into theoxidant gas and flow in suspension during combustion towards themelt/quench chamber 902 as they become heated and eventually molten,above liquid phase transition. The gas may include an oxidant gas,including but not limited to oxygen, air mixed with a combustible fuel,including but not limited to propane, methane, liquid hydrocarbon fuels,coal, syngas, biomass, coal-water slurries, and mixtures thereof.Preferably the flame 901 is stabilized by an annular flow of quench air904 that protects the melt/quench chamber 902 and prevents particlesfrom sticking to inner wall 905 of the melt/quench chamber 902.

In the apparatus 900, molten particles are next quenched by cooling inair as the suspension becomes turbulent at an end of the melt/quenchchamber 902. Cooling/quenching of the molten particles may be providedby cool quench air introduced directly into the melt/quench chamber 902,and/or by an optional cooling system, for instance a liquid cooling looparound a quenching section of the melt/quench chamber 902 (not shown).The molten particles may be quenched or cooled to a non-crystallinesolid powder, and may result in a powder comprising microspheroidalglassy particles. The apparatus may further comprise an optional cycloneseparator operated under suction from a centrifugal blower to collectthe powder comprising microspheroidal glassy particles (not shown).

The apparatus 900 or similar can be used in various systems to produce aglassy microspheroidal cementitious reagent. FIG. 8 illustrates oneembodiment of a schematic process flow diagram of an exemplary system800 for producing a glassy microspheroidal cementitious reagent, whichin some cases, produces a microspheroidal glassy reagent powder 109.

In the embodiment of FIG. 8 , the system 800 comprises a milling circuit801 to obtain an aluminosilicate feedstock powder 101. Coarsealuminosilicate feedstock material 802 is fed to a jaw crusher or impactmill 803 to produce a suitably sized feed 804 allowing fine grinding ina ball mill 805. The resulting product is a finely dividedaluminosilicate feedstock powder 101.

The finely divided aluminosilicate feedstock powder 101 is nextentrained in an oxidant gas (e.g. oxygen) 807, and mixed with acombustible fuel (e.g. propane) 808 in a burner 809 that is fitted witha liquid cooling loop 810 for long torch life. Ambient temperaturequench air 811 is introduced, preferably near the burner 809, and flowsdown the outside of the melt/quench chamber 812 walls for preventingmolten particles from sticking to the walls of the burner 809. Wallcooling may be provided by the quench air, and/or by an optional liquidcooling loop 813. Molten particles are quenched by cool quench air asthe suspension becomes turbulent at the end of the melt/quench chamber.A cyclone separator 814, operated under suction from a centrifugalblower 815 may be used to collect the microspheroidal glassy reagentpowder 109.

The apparatus of FIG. 9 and system of FIG. 8 were successfully used toproduce solid microspheroidal glassy particles, and cementitious reagentcomprising the same, as defined herein and described in the followingexamples. The operating parameters involved an approximatelystoichiometric combustion of propane and oxygen gases (exact mass rationot measured). Powdered feedstock 101 entered the burner from apneumatic disperser fed by a vibratory feeder. The suspension offeedstock and combustion air consisted of approximately an equal mass ofoxygen and powdered feedstock; for example, 1 g of aluminosilicatefeedstock suspended in 1 g of oxygen.

Those skilled in the art will appreciate that the illustrated apparatus,system and parameters are ones of many potential useful apparatus andsystem encompassed by the present invention. For instance, in alternateembodiments, the solid particles fly in suspension in a carrier gas andare heated by one or more energy sources. The energy for melting may beprovided by one or a combination of suitable high-temperature heatsources such as plasma (arc discharge or inductively coupled),electrical induction heating, electrical resistance heating, microwaveheating, solar irradiation, or heat from chemical reactions (e.g.combustion). Several of these energy sources may lower the CO₂ footprintof the process, but costs of CO₂ emissions must be weighed against theunique costs of each energy source. In many jurisdictions today, thecheapest energy sources are based on combustible hydrocarbon fuels.Therefore, the choice of energy source is mostly dictated by price andcost of CO₂ emissions in a given jurisdiction. Current economic andpolitical factors dictate that preferably, the solid particles fly insuspension in a gas such that combustion heats the solid particles to atemperature above the liquid phase transition.

Although an oxygen-fuel burner was used in the examples provided, thoseskilled in the art will appreciate that the choice of burner fuels is ofonly secondary importance as long as adequate heating occurs. Any sourceof heat from combustion, plasma, concentrated solar power, nuclear, andothers, are possible.

In some embodiments, an air-fuel burner is preferable to avoid the costof oxygen enrichment. When air, consisting of only about 23 wt % oxygen,is combusted with fuels (propane or methane for example) the air-fuelratio is much higher (˜4-5×) to maintain an approximately stoichiometriccombustion. A higher air-fuel ratio results in lower flame temperatures.Therefore, it is preferable to adjust accordingly the feedstock powdermass flow to ensure the particles are heated beyond their solidus, andpreferably near or beyond their liquidus temperature (1000-1600° C., andcommonly greater than 1200° C.).

FIG. 10 illustrates another embodiment of an apparatus and system forin-flight melting/quenching in accordance with embodiments describedherein. Feedstock 101 passes through valve 1002 and enters cyclone 1003where it is preheated by exchanging heat with hot gases flowing throughpipe 1026. Valve 1004 meters feedstock powder into hot gas (e.g.combustion air) flowing through pipe 1025. Combustion air and feedstocksuspension is conveyed through a burner 1005 wherein combustible gas isintroduced through pipe 1006. A cylindrical melting chamber 1007 isconfigured to receive a hot stream of gas (e.g. combustion gases)entrained with aluminosilicate particles in various stages of melting1008. The melting chamber 1007 comprises a cylindrical shell 1009 ofsuitable material such as steel, and an inner lining of suitablerefractory material 1010. The melting chamber 1007 is also protectedinternally by a stream of cool air (primary quench air) 1011 injectedfrom an upper distribution ring 1012. Cooling air flows inside themelting chamber 1007 around inner chamber walls in a laminar or swirlingflow 1013 without mixing significantly with the central stream of moltensuspended particles 1008. This airflow also protects the innerrefractory lining 1010 and limits heat loss.

Molten particles 1008 next enter a quenching chamber or quench zone 1014where particles interact with primary quench air 1013 and optionallysecondary cool quench air 1015 that passes through a distributor 1016and is injected 1017 into the quenching chamber 1014.

Quenched, hot solid particles 1018 flow suspended through pipe 1019 andare separated from hot gases in a cyclone separator 1020. Hot solidglassy particles pass through valve 1021, exchange heat with coolcombustion air 1024, and are separated in combustion air preheat cyclone1022. Valve 1023 regulates pressure and allows collection ofmicrospheroidal glassy product 109. The cyclone separators 1003,1020,1022 also function as solid/gas heat exchangers for important heatrecovery loops that increase energy efficiency of the process. Incyclone 1020, hot gases from the melting chamber 1007 are separated fromsolids and these gases preheat cooler feedstock powder 101 beforeseparation in cyclone 1003. The heat-exchanged exhaust gas 1027 reportsto a suitable exhaust system (for example, a baghouse and blower) orpasses on to further stages of heat exchange cyclones. In cyclone 1022,hot quenched particles 1018 exchange heat with cool combustion air 1024and the preheated combustion air is used to convey preheated feedstockpowder into the melting chamber 1007 thereby considerably reducing theamount of energy that must be added to achieve melting of the suspendedparticles.

EXAMPLES Example 1: Yield Stress Reduction with Synthetic SpheroidalParticles

To demonstrate the improvement to geopolymer cement mix viscosity, thefollowing procedure was employed. A commercially-available pulverizedvolcanic glass powder of oxide composition SiO2-73.77%; Al2O3-11.82%,Fe2O3-1.42%; MgO-0.1%; CaO-0.28%; Na2O-4.22%; K2O-4.09% was purchasedhaving a D[3,2] mean particle diameter of 10 micrometers and angularmorphology typical of finely ground powders. The volcanic glass powdersample 402 (FIG. 4 ) was processed by the presently disclosed method ofin-flight melting in order to create an optimally molten/quenched powder403, having a D[3,2] mean particle size of 11 micrometers, andsubstantially spheroidal morphology characterized by roundness R >8 (seeFIG. 4 ). More specifically, the natural volcanic glass powder (angularmorphology) was processed by the apparatus shown in FIG. 8 and FIG. 9 .The burner was a commercial oxygen-propane burner model QHT-7/hA fromShanghai Welding & Cutting Tool Works with modified powder feeding, theburner fired into a steel melt chamber with water-cooled walls, andparticle temperatures exceeded the mean liquidus temperature of thematerial, about 1300° C. as estimated from compositional data. It isinterpreted that liquidus temperature was exceeded based on i) themicrospheroidal morphology that results from surface tension in liquidphase, ii) homogeneous composition (under backscattered electronimaging) and iii) the absence of unmolten or partially molten particlesin the final reagent. In this experiment, the burner was not sealedtightly to the melt chamber, and thereby cool quench air was allowed torush in along the walls of the melt chamber, only quenching the moltenentrained powder after sufficient residence time to allow melting.Quenched hot powder was separated from hot combustion gases with acyclone as shown in FIG. 8 and glass powder was collected for testing.The resulting product in this example is a highly spherical syntheticglass (D[3,2]=11 micrometer) of equivalent composition and nearlyequivalent particle size distribution (FIG. 4 ) as the raw feedstock.

The microspheroidal mineral glass powder has a molar Si/(Al, Fe³⁺) of19.68, and molar cementitious reagent formula of(Ca,Mg)_(0.12).(Na,K)_(0.89).(Al, Fe³⁺)_(i).Si_(19.68) and CaO of 0.28wt. % (CaO,MgO of 0.38%) .

The experiment compares two geopolymer reagents with particles ofequivalent composition and nearly equivalent particle size distribution(confirmed by laser diffraction particle size analysis, FIG. 4 ). Theonly drastically changed variable is particle morphology.

The powders were mixed separately as geopolymer binder pastes using thefollowing mix design optimized for minimal water use for angularvolcanic glass (“Mix A”):

A 99.5 g mixture is made containing 1.77 moles of water, 0.12 molesNa₂O+K₂O, 0.82 moles SiO₂ and 0.08 moles Al₂O₃+Fe₂O₃. The source ofAl₂O₃+Fe₂O₃ is the cementitious reagent glass or volcanic glass. Thesource of SiO₂ is also the cementitious reagent or volcanic glass andpotassium silicate. The source of potassium oxide is potassium silicateand potassium hydroxide. The oxide mole ratios of each mix are providedin Table 1, shown below.

Spheroidal Mix A was too fluid when mixed at the same mass proportionsas Angular Mix A, which had very poor workability even at very highwater contents of 40 wt. % H₂O. Surprisingly, Spheroidal Mix B,containing only 15 wt. % H₂O, had excellent workability as indicated bylow yield stress of ˜6 Pa.

The glassy spheroidal powder was remixed with an identical amount ofsolid reagent, but lower proportions of silicate hardener and water(“Mix B”):

A 79 g mixture was made containing 0.73 moles of water, 0.11 molesNa₂O+K₂O, 0.8 moles SiO₂ and 0.08 moles Al₂O₃+Fe₂O₃. The source ofAl₂O₃+Fe₂O₃ is the spheroidal cementitious reagent. The source of SiO₂is also the spheroidal cementitious reagent and potassium silicate. Thesource of potassium oxide is potassium silicate and potassium hydroxide.The oxide mole ratios of each mix are provided in Table 1, shown below.

A mini-cone slump test (as described by Tan et al. 2017) was employed todetermine the approximate yield stress for the angular powder Mix A(spread radius 24 mm), and the spheroidal powder Mix B (spread radius 60mm). The angular powder produced a non-shear-flowing mass withapproximate yield stress of 425 Pa or greater (as calculated by slumpflow equation 10 elaborated in Pierre et al. 2013 (Pierre, A., Lanos,C., & Estellé, P. (2013). Extension of spread-slump formulae for yieldstress evaluation. Applied Rheology, 23(6), 36-44). Surprisingly, thespheroidal mix had only 41% of the molecular water content of theangular mix (including water in soluble silicate hardener) yet producedan easily pourable resinous fluid with yield stress of onlyapproximately 6.5 Pa (as calculated by the spreading flow equation 2 inTan et al. 2017 (Tan, Z., Bernal, S. A., & Provis, J. L. (2017).Reproducible mini-slump test procedure for measuring the yield stress ofcementitious pastes. Materials and Structures, 50(6), 235).

TABLE 1 Oxide mole ratios of mixes Angular Spheroidal Spheroidal Molarratio “Mix A” “Mix A” “Mix B” (Na₂O, K₂O)/SiO₂  0.14  0.14  0.14SiO₂/(Al₂O₃, Fe₂O₃)  11.72  11.72   10 H₂O/(Al₂O₃, Fe₂O₃) 22.125 22.1259.125 (Na₂O, K2O)/(Al₂O₃,  1.63  1.63 1.375 Fe₂O₃) H₂O/(Na₂O, K₂O) 15.65  15.65  7.05 H₂O in paste (wt. %)    40%    40%   15% YieldStress (Pa)   425    <1    6

Angular Mix A and Spheroidal Mix B were heated and cured in a sealedcontainer at 80 degrees Celsius for 6 hours. The angular paste hardenedpoorly, likely due to the high water content, while the spheroidal pastehardened to a ceramic-like solid with a fine glossy surface.

Example 2: Basalt “FC”

Oligocene basaltic rock was sampled in Vancouver, BC. The mineralogy ofthe rock is dominated by plagioclase, diopside and a clay-like phasethat is likely a weathering product (Table 2, determined by XRD withRietveld refinement). The major element oxide composition is provided inTable 3.

TABLE 2 Mineralogy of basalt sample Phase Weight % albite-low (calcian)56.2 diopside 13.5 clay (montmorillonite model) 12.5 forsterite(ferrian) 5.0 Illite/muscovite 2M1 2.6 lizardite 1T 1.7 ilmenite 1.7quartz 1.6 calcite 1.5 ulvospinel (ferrian) 1.4

TABLE 3 Oxide Composition of basalt “FC” (XRF) Oxide Weight % SiO₂ 48.13Al₂O₃ 15.97 Fe₂O₃ 11.99 MnO 0.16 MgO 7.83 CaO 9.51 Na₂O 2.77 K₂O 0.5

The basalt was crushed in a jaw crusher, then pulverized in a disc mill,and further reduced in a ring mill to a powder with mean particle sizeof approximately 10 μm. The powder was fed through a vitrificationapparatus that heated the material through the liquid transition toapproximately 1450° C., followed by a rapid quenching step. Theresulting glass was 96.7% X-ray amorphous (Table 4).

TABLE 4 XRD-Rietveld analysis of basalt glass (corundum spike) PhaseWeight % amorphous 96.7 iron-alpha (from grinding media) 1.9 quartz 1.4

The microspheroidal basalt glass powder has a molar Si/(Al, Fe³⁺) of6.93, and molar cementitious reagent formula of(Ca,Mg)_(3.15).(Na,K)_(0.21).(Al, Fe³⁺)₁.Si_(6.93) and CaO of 9.51 wt. %(CaO,MgO of 17.3%) .

Individual particles were observed to be highly spherical and meanroundness R is >0.8 (as defined previously), and D[3,2] is 10.5 μm.

A 131 g mixture is made containing 1.31 moles of water, 0.1 molesNa₂O+K₂O, 0.88 moles SiO₂ and 0.24 moles Al₂O₃+Fe₂O₃. The source ofAl₂O₃+Fe₂O₃ is the microspheroidal basalt powder prepared above. Thesource of SiO₂ is also the basalt powder and potassium silicate. Thesource of potassium oxide is potassium silicate and potassium hydroxide.The oxide mole ratios are provided in Table 5, shown below.

TABLE 5 Oxide mole ratios (Na₂O, K₂O)/SiO₂ 0.11 SiO₂/(Al₂O₃, Fe₂O₃) 3.67H₂O/(Al₂O₃, Fe₂O₃) 5.45 (Na₂O, K2O)/(Al₂O₃, Fe₂O₃) 0.42 H₂O/(Na₂O, K₂O)13.76 Yield Stress (Pa) 21.7

A mini slump cone test was performed on the geopolymer cement paste andresulted in a flow diameter of 98.4 mm and a calculated yield stress of21.7 Pa. 110 g of sand was added to the paste, followed by 6 hours ofsealed curing at 80 degrees Celsius. The compressive strength of amortar sample cube was determined to be 19 MPa.

Example 3: Basalt “BD”

A commercially available powdered basalt “BD” has the oxide compositionprovided in Table 6, shown below.

TABLE 6 Oxide Composition of basalt “BD” (XRF) Oxide Weight % SiO₂ 49.77Al₂O₃ 14.42 Fe₂O 11.18 MgO 4.38 CaO 9.66 Na₂O 2.62 K₂O 0.63

The powder was fed through a vitrification apparatus that heated thematerial through a liquid phase change to approximately 1450° C.,followed by a rapid quenching step. Successful melting through theliquid phase was demonstrated for most particles by a highly sphericalbulk particle morphology.

The microspheroidal basalt reagent powder “BD” has a molar Si/(Al, Fe³⁺)of 7.84, and molar cementitious reagent formula of(Ca,Mg)_(2.66).(Na,K)_(0.23).(Al, Fe³⁺)₁.Si_(7.84) and CaO of 9.66 wt. %(CaO,MgO of 14.04%). Individual particles were observed to be highlyspherical and smooth, roundness R is greater than 0.8, and D[3,2] is 8.0μm as measured by laser diffraction.

A 116 g mixture was made containing 1.53 moles of water, 0.09 molesNa₂O+K2O, 0.75 moles SiO₂ and 0.17 moles Al₂O₃+Fe₂O₃. The source ofA1203 +Fe2O3 is the microspheroidal basalt powder prepared above. Thesource of SiO₂ is also the basalt powder and potassium silicate. Thesource of potassium oxide is potassium silicate and potassium hydroxide.The oxide mole ratios are provided in Table 7.

TABLE 7 Oxide mole ratios (Na₂O, K₂O)/SiO₂ 0.11 SiO₂/(Al₂O₃, Fe₂O₃) 4.41H₂O/(Al₂O₃, Fe₂O₃) 9.00 (Na₂O, K₂O)/(Al₂O₃, Fe₂O₃) 0.53 H₂O/(Na₂O, K₂O)18.06

110 g of sand was added to the mixture, and the sample was cast intocube molds, followed by 6 hours of sealed curing at 80 degrees Celsius.From three samples, the mean compressive strength of the mortar wasdetermined to be 27.4 MPa with standard deviation of 2.22 MPa.

Example 4: Coal Tailings

A coal tailings sample acquired from Cape Breton, NS consists ofapproximately 60% residual coal and 40% mineral material. The inorganicfraction has the oxide composition provided in Table 8, shown below.

TABLE 8 Oxide Composition of Coal Tailings (XRF) Oxide Weight % (avg. of2 samples) SiO₂ 52.48 Al₂O₃ 21.76 Fe₂O₃ 15.74 MgO 1.29 CaO 1.57 Na₂O0.28 K₂O 3.08

Dried coal tailings with measured D[3,2] of 9.9 μm were fed through avitrification apparatus that combusted excess coal and heated theinorganic material through a liquid phase change to approximately 1450°C., followed by a rapid quenching step. The coal fraction in thefeedstock added considerable energy to the process: the flame powerincreased at least 46% processing coal tailings compared to an “inert”basalt processed at the same mass flow rate.

Successful melting through the liquid phase was demonstrated forinorganic particles by a highly spherical bulk particle morphology, withmean roundness (R)>0.8, and D[3,2] is 11.2 μm.

The microspheroidal coal tailings reagent powder has a molar Si/(Al,Fe³⁺) of 5.66, and molar cementitious reagent formula of(Ca,Mg)_(0.38).(Na,K)_(0.10)Al, Fe³⁺)₁.Si_(5.66) and CaO of 1.7 wt. %(CaO,MgO of 2.56%) .

A 45 g mixture is made containing 0.57 moles of water, 0.04 molesNa₂O+K₂O, 0.42 moles SiO₂ and 0.12 moles Al₂O₃+Fe₂O₃. The source ofA1203 +Fe2O3 is the coal tailings microspheroidal powder prepared above.The source of SiO₂ is also the coal tailings powder and sodium silicate.The source of sodium oxide is sodium silicate and sodium hydroxide. Theoxide mole ratios are provided in Table 9, shown below.

TABLE 9 Oxide mole ratios (Na₂O, K₂O)/SiO₂ 0.11 SiO₂/(Al₂O₃, Fe₂O₃) 4.45H₂O/(Al₂O₃, Fe₂O₃) 4.85 (Na₂O, K₂O)/(Al₂O₃, Fe₂O₃) 0.49 H₂O/(Na₂O, K₂O)14.25

The mixture was cast into a cube mold, followed by 6 hours of sealedcuring at 80 degrees Celsius. The sample was demolded and found to havea compressive strength of 21 MPa and a glossy ceramic-like surface.

Example 5: Dredged Sediment

A sediment sample was acquired from the middle of Vancouver Harbour, BCto represent an example of dredged sediment. The sample has the oxidecomposition provided in Table 10, shown below.

TABLE 10 Oxide Composition of sediment (XRF) Oxide Weight % SiO₂ 67.06Al₂O₃ 12.69 Fe₂O₃ 5.62 MgO 2.4 CaO 2.98 Na₂O 2.69 K₂O 1.64

The sample was dried and found to have a mass median diameter, D50, of47 μm. Next, the sample was sieved to remove particles not passing 75μm.

This powder was fed through a vitrification apparatus that heated thematerial through a liquid phase change to approximately 1450° C.,followed by a rapid quenching step.

Successful melting through the liquid phase was demonstrated for mostparticles by a highly spherical bulk particle morphology. Themicrospheroidal sediment reagent powder has a molar Si/(Al, Fe³⁺) of11.49, and molar cementitious reagent formula of(Ca,Mg)_(1.55).(Na,K)_(0.51).(Al, Fe³⁺)₁.Si_(11.49) and CaO of 4.42 wt.% (CaO,MgO of 7.14%).

Individual particles are highly spherical and smooth, with meanroundness (R) >0.8, and D[3,2] of 11.8 μm.

A 98 g mixture is made containing 0.89 moles of water, 0.09 molesNa₂O+K₂O, 0.8 moles SiO₂ and 0.13 moles Al₂O₃+Fe₂O₃. The source ofAl₂O₃+Fe₂O₃ is the microspheroidal sediment powder prepared above. Thesource of SiO₂ is also the sediment powder and potassium silicate. Thesource of potassium oxide is potassium silicate and potassium hydroxide.The oxide mole ratios are provided in Table 11.

TABLE 11 Oxide mole ratios (Na₂O, K₂O)/SiO₂ 0.12 SiO₂/(Al₂O₃, Fe₂O₃)6.15 H₂O/(Al₂O₃, Fe₂O₃) 6.85 (Na₂O, K₂O)/(Al₂O₃, Fe₂O₃) 0.69 H₂O/(Na₂O,K₂O) 9.19

110 g of sand was added to the mixture, and the sample was cast into acube mold, followed by 6 hours of sealed curing at 80 degrees Celsius.The compressive strength of the mortar cube was determined to be 25 MPa.

Example 6: Copper Mine Tailings

A sample of copper porphyry flotation tailings was acquired fromArgentina to represent an example of a globally abundant aluminosilicatewaste material. The sample has the oxide composition provided in Table12, shown below.

TABLE 12 Oxide Composition of sediment (XRF) Oxide Weight % SiO₂ 70.98Al₂O₃ 15.26 Fe₂O₃ 2.64 MgO 1.18 CaO 1.09 Na₂O 2.75 K₂O 3.44

The sample was sieved to remove particles not passing 75 μm. This powderwas fed through a vitrification apparatus that heated the materialthrough a liquid phase change to approximately 1450° C., followed by arapid quenching step. Successful melting through the liquid phase wasdemonstrated for most particles by a highly spherical bulk particlemorphology.

The microspheroidal mine tailings reagent powder has a molar Si/(Al,Fe³⁺) of 14.2, and molar cementitious reagent formula of(Ca,Mg)_(0.6).(Na,K)_(0.5).(Al, Fe³⁺)₁.Si_(14.2) and CaO of 1.94 wt. %(CaO,MgO of 4.87%) .

Individual particles are highly spherical and smooth, mean roundness (R)is greater than 0.8, and D[3,2] is 11.4 μm.

A 103.6 g mixture is made containing 0.76 moles of water, 0.11 molesNa₂O+K₂O, 1.04 moles SiO₂ and 0.13 moles Al₂O₃+Fe₂O₃. The source ofAl₂O₃+Fe₂O₃ is the microspheroidal tailings powder prepared above. Thesource of SiO₂ is also the tailings powder and potassium silicate. Thesource of potassium oxide is potassium silicate and potassium hydroxide.The oxide mole ratios are provided in Table 13, shown below.

TABLE 13 Oxide mole ratios (Na₂O, K₂O)/SiO₂ 0.10 SiO₂/(Al₂O₃, Fe₂O₃)8.64 H₂O/(Al₂O₃, Fe₂O₃) 7.78 (Na₂O, K₂O)/(Al₂O₃, Fe₂O₃) 0.89 H₂O/(Na₂O,K₂O) 9.67

110 g of sand was added to the mixture, and the sample was cast into acube mold, followed by 6 hours of sealed curing at 80 degrees Celsius.The compressive strength of the mortar cube was determined to be 18 MPa.

Example 7: Waste Concrete

Structural concrete cores were sampled from a mid-rise condominiumconstruction site in Vancouver, BC. The material has the oxidecomposition provided in Table 14, shown below.

TABLE 14 Oxide Composition of a Structural Concrete (XRF) Oxide Weight %SiO₂ 56.61 Al₂O₃ 13.94 Fe₂O₃ 5.15 MgO 1.42 CaO 12.55 Na₂O 3.55 K₂O 1.48

The sample was sieved to remove particles not passing 75 μm. This powderwas fed through a vitrification apparatus that heated the materialthrough a liquid phase change to approximately 1450° C., followed by arapid quenching step.

Successful melting through the liquid phase was demonstrated for mostparticles by a highly spherical bulk particle morphology.

The microspheroidal concrete reagent powder has a molar Si/(Al, Fe³⁺) of12.3, and molar cementitious reagent formula of(Ca,Mg)_(3.06).(Na,K)_(0.7).(Al, Fe³⁺)₁.Si_(12.3) and CaO of 12.55 wt. %(CaO,MgO of 13.97%).

Individual particles are highly spherical and smooth, mean roundness (R)is greater than 0.8, and D[3,2] is 10.0 μm.

A 100 g mixture is made containing 1.27 moles of water, 0.08 moles Na₂O+K₂O, 0.73 moles SiO₂ and 0.13 moles Al₂O₃+Fe₂O₃. The source ofAl₂O₃+Fe₂O₃ is the microspheroidal concrete powder prepared above. Thesource of SiO₂ is also the concrete powder and potassium silicate. Thesource of potassium oxide is potassium silicate and potassium hydroxide.The oxide mole ratios are provided in Table 15, shown below.

TABLE 15 Oxide mole ratios (Na₂O, K₂O)/SiO₂ 0.11 SiO₂/(Al₂O₃, Fe₂O₃)7.59 H₂O/(Al₂O₃, Fe₂O₃) 10.79 (Na₂O, K₂O)/(Al₂O₃, Fe₂O₃) 0.86 H₂O/(Na₂O,K₂O) 15.46

100 g of sand was added to the mixture, and the sample was cast into acube mold, followed by 6 hours of sealed curing at 80 degrees Celsius.The compressive strength of the mortar cube was determined to be 27 MPa.

Example 8: Quarried Aggregate

Granodioritic crusher dust from an aggregate quarry near Vancouver,Canada was sampled for the following experiment. The sample has an oxidecomposition (SEM-EDX) of approximately SiO₂-73%; A₂O₃-15%, Fe₂O₃-3%;MgO-0%; CaO-2%; Na₂O-3%; K₂O-4%. The rock was further crushed and milledto a fine powder completely passing 75 μm.

The resulting powder was processed by an in-flight vitrificationapparatus that heated the material through a liquid phase change toapproximately 1450° C., followed by a rapid quenching step.

Successful melting through the liquid phase was demonstrated for mostparticles by a highly smooth and spherical bulk particle morphology.

Individual particles are highly spherical and smooth, mean roundness (R)is greater than 0.8, and D[3,2] is 9.3 μm. The microspheroidalgranodiorite glass reagent powder has a molar Si/(Al, Fe³⁺) of 16.0, andmolar cementitious reagent formula of (Ca,Mg)_(2.5).(Na,K)_(4.4).(Al,Fe³⁺)₁.Si_(16.0) and CaO of 2 wt. % (CaO,MgO of 2%).

A 105 g mixture is made containing 1.53 moles of water, 0.1 molesNa₂O+K₂O, 0.93 moles SiO₂ and 0.12 moles Al₂O₃+Fe₂O₃. The source ofAl₂O₃+Fe₂O₃ is the microspheroidal aggregate powder prepared above. Thesource of SiO₂ is also the aggregate powder and potassium silicate. Thesource of potassium oxide is potassium silicate and potassium hydroxide.The oxide mole ratios are provided in Table 16.

TABLE 16 Oxide mole ratios (Na₂O, K₂O)/SiO₂ 0.1 SiO₂/(Al₂O₃, Fe₂O₃) 8.0H₂O/(Al₂O₃, Fe₂O₃) 10.8 (Na₂O, K₂O)/(Al₂O₃, Fe₂O₃) 0.9 H₂O/(Na₂O, K₂O)12.9

The mixture above was cast as a paste into a cube mold, followed by 24hours of sealed curing at 80 degrees Celsius. The compressive strengthof the paste cube was determined to be 11 MPa, showing that the materialgains strength with heat curing, as expected. The lower relativestrength can be explained by the omission of sand (as in mortar), andhigher unmolten quartz mineral content compared to other examples(quartz melts at >1600° C.), which acts as a relatively inert filler.

SUMMARY OF EXAMPLES 1 TO 8

Table 17 below summarizes the main findings of examples 1-8 and alsoprovides a comparison against the performance of two fly ashes; onecommercially available Type F fly ash that has been beneficiated (B-FA),and fly ash of Type F composition sampled directly from a coal powerplant in Nova Scotia, Canada. A visual representation of the roundness Rdistributions is provided in FIG. 5 .

TABLE 17 Summary of Examples 1 to 8 Particle Mortar Size CompressiveD[3,2] R (Roundness) Strength Example Sample Material Type (μm) MeanStDev n (MPa) 1 PUM-1 Pumice Feedstock 0.79 0.21 201 <1 Processed 11.00.86 0.11 128 11 2 B-FC Basalt Feedstock 0.80 0.15 151 Processed 10.50.89 0.10 160 19 3 BD-1 Basalt Feedstock 0.75 0.16 1326 Processed 8.00.91 0.08 230 27 4 VJ Coal Feedstock 0.73 0.17 561 Tailings Processed11.2 0.89 0.06 652 21 5 FRS Sediment Feedstock 0.79 0.66 2383 CopperMine 6 LA-01 Tailings Feedstock 0.68 0.21 1414 Processed 11.4 0.90 0.08294 18 7 SC-01 Demolished Feedstock 0.78 0.14 627 Concrete Processed10.0 0.88 0.10 238 27 8 SV- Felsic Feedstock 0.78 0.16 2564 AGGAggregate Processed 9.3 0.88 0.07 951 11 L-FA Fly Ash Direct from 3.90.83 0.13 1505 2.2 (Type F) Power Plant B-FA Fly Ash Beneficiated 5.10.87 0.07 797 23 (Type F) R—roundness (unitless), as defined byTakashimizu & Iiyoshi (2016), n—number of particles analyzed.

Example 9: Use of Synthetic Cementitious Reagent as Alternative SCM

Microspheroidal basalt sample “BD” of Example 3 above was furtherprocessed by pulverizing the powder in a ring mill for 5 minutes,causing the coarsest particles to break and thereby increase reactivesurface area. The D[3,2] particle size was determined to be 3.6 μm bylaser diffraction analysis. Interestingly, small spheres <10 μm tend toact as ball bearings in the mill and resist breakage. The reagent'sstrength activity index was compared to a commercially availablehigh-quality Type F fly ash with an oxide composition SiO₂-52.09%;Al₂O₃-18.58%, Fe₂O₃-4.25%; MgO-2.98%; CaO-10.25%; Na₂O-6.03%; K₂O-1.72%.

Following ASTM C618, 50 mm cubes were cast of a Portland cement controlmix, Portland cement with fly ash (20% and 40% replacement), andPortland cement with cementitious reagent BD powder (also 20% and 40%replacement). Table 18 provides the compressive strength results at 7and 28 days. The performance of the BD mix at 20% replacement wascomparable with the commercial Type F fly ash and the strength activityindex was acceptable. The BD mix was easily workable and mixed withouttrouble. Notably, both the BD reagent and fly ash produce very useablemortar strengths greater than 40 MPa after 28 days at 40% replacement ofPortland cement. BD cementitious reagent can therefore be considered asuitable fly ash replacement in terms of compressive strength.

TABLE 18 Strength of Portland cement with cementitious reagent BD powderStrength Activity Index Ratio to Ratio to Compressive Strength controlcontrol 7 days 28 days (7 days) (28 days) Control 45.4 60.8 FA-20 38.648.4 85% 79% FA-40 29.2 42 BD-20 38.4 50.8 84% 83% BD-40 26.4 44 Minimumrequirement of ASTM C618 75% 75%

Cementitious Material

According to some embodiments, a novel method of production and uses ofcementitious reagents, geopolymer reagents and supplementarycementitious materials (SCM) provides significant advantages over theknown methods and formulas.

According to some embodiments, a cementitious reagent comprises theoxide Formula 1:(CaO,MgO)a.(Na₂O,K₂O)b.Al₂O₃,Fe₂O₃)c.(SiO₂)d   [Formula 1]

-   -   wherein a is about 0 to about 4,    -   b is about 0.1 to about 1,    -   c is 1, and    -   d is about 1 to about 15.

Advantageously, the cementitious reagent in accordance with the presentinvention is formulated from abundant rocks, minerals and compounds ofsuitable composition. Preferably the CaO content is lower that about 30wt. % in order to reduce the CO2 impact of cement.

In some embodiments, the cementitious reagent is in the form of anon-crystalline solid. In embodiments, the cementitious reagent is in apowder form comprising a particle size distribution with a D50 (mediandiameter) of approximately 20 μm or less, or preferably 10 μm or less.

In embodiments, the cementitious reagent comprises at least one of thefollowing properties: a content of 45%-100%, and preferably 90-100%,X-ray amorphous solid; and molar composition ratios of(Ca,Mg)₀₋₁₂.(Na,K)_(0.05-1).(Al, Fe3+)₁.Si₁₋₂₀.

In some embodiments, the cementitious reagent comprises less than about10 wt. % CaO. In another embodiment, the cementitious reagent comprisesmore than about 30 wt. % CaO. The composition of cementitious reagentwith respect to molar ratio of (Na, K), and Ca may be varied to obtaincertain advantages depending on the binder requirements. For example, acementitious reagent with less than about 10 wt. % CaO is suitable foruse in heat-cured geopolymer and as a fly ash substitute. In thealternative, a cementitious reagent with greater than about 30 wt. % CaOhas hydraulic properties and may be added to geopolymer resin to allowambient-temperature curing of geopolymer cement, and directly replacesblast furnace slag in blended Portland cement.

In some embodiments, the cementitious reagent is a low-calciumcontaining cementitious reagent with a molar composition of Si/(Fe³⁺,Al)between 1-20, and with a CaO content of about 10 wt. % or less.Preferably such cementitious reagent is 40-100% X-ray amorphous, morepreferably about 80- about 100% X-ray amorphous, even more preferably100% non-crystalline. Such low-calcium containing cementitious reagentmay find numerous commercial applications, for instance, as a pozzolanicadmixture in hydraulic cement, and/or as a reagent in geopolymer bindersand cements.

In another embodiment, the cementitious reagent is a high-calciumcontaining cementitious reagent with a molar composition of Si/(Fe³⁺,Al)between 1-20, and CaO content of about 10- about 50 wt. %, preferablyabout 20- about 45 wt. %. Preferably such cementitious reagent is40-100% X-ray amorphous, more preferably about 80- about 100% X-rayamorphous, even more preferably 100% non-crystalline. Such ahigh-calcium containing cementitious reagent may find numerouscommercial applications, for instance as a hydraulic admixture inblended hydraulic cement, and/or as a reagent in geopolymer binders andcements.

In another embodiment, the cementitious reagent is anintermediate-calcium containing cementitious reagent with a molarcomposition of Si/(Fe³⁺,Al) between 1-20, and CaO content of about 10-about 20 wt. %. Preferably such cementitious reagent is about 40-1 00%X-ray amorphous, and preferably about 80- about 100% X-ray amorphous,and even more preferably 100% non-crystalline. Such anintermediate-calcium containing cementitious reagent may find numerouscommercial applications, for instance as a cementitious reagent withdesirable intermediate hydraulic and pozzolanic properties.

One important advantage of optimizing Na/K in the cementitious reagentin accordance with the present is in: 1) SCM applications where freelime in hydraulic cement will exchange with soluble alkalis andcoordinate with sialate molecules from cementitious reagent to createsome extent of relatively stable alkali aluminosilicate polymerizationthat greatly improves chemical properties of traditional hydrauliccements; and 2) the fact that geopolymer reagents with significant Na/Kcontents require less soluble silicate hardener than would otherwise benecessary, thus decreasing the soluble silicate requirement (and cost)of a geopolymer mix design.

Method of Preparation

In some embodiments, aluminosilicate materials are selected as afeedstock for producing cementitious reagent. FIG. 1 shows exemplarysteps necessary to produce cementitious reagent from aluminosilicatematerials, in accordance with an embodiment of the present invention.

Briefly, an aluminosilicate material 101 is selected, and its chemicalcomposition is analyzed 102 and evaluated. The feedstock may be analyzedby any suitable quantitative or semi-quantitative methods such as XRF,XRD with Rietveld Refinement, LIBS, EDS, wet chemical analysis, andvarious other existing methods to determine the feedstock elementalcomposition.

If the selected composition is not acceptable, the material is amended,blended (e.g. in a vessel prior to thermochemical processing), or sorted103, for example, through addition of a composition adjustment material104. As used herein, the term “composition adjustment material” refersto any solid or liquid material with a composition suitable forpreferentially altering the bulk composition of aluminosilicate materialwith respect to one or several of the elements Ca, Na, K, Al, Fe, andSi.

As described above, composition adjustment materials that introducecalcium (Ca) may be comprised of CaCO₃, Ca(OH)₂, CaO, CaCl , calciumsilicate minerals and compounds, calcium aluminum silicate minerals andcompounds, waste portland cement products, wollastonite, gehlenite, andother melilite group mineral compositions.

As described above, composition adjustment materials that introducealuminum (Al) may be comprised of aluminous rocks, minerals, soils,sediments, by-products, and compounds including one or more ofkaolinite, halloysite and other aluminum-rich/alkali-poor clay minerals,Al₂SiO₅ polymorphs, chloritoid, staurolite, garnet, corundum, mullite,gehlenite, diaspore, boehmite, gibbsite, and nepheline and otherfeldspathoids. Other materials that may be used include aluminum metal,bauxite, alumina, red mud (alumina refinery residues).

As described above, composition adjustment materials that introduce iron(Fe) may be comprised of iron-rich rocks, minerals, soils, sediments,by-products, and compounds such as olivine, chlorite minerals(chamosite, clinochlore, etc.), pyroxenes, amphiboles, goethite,hematite, magnetite, ferrihydrite, lepidicrocite and other ironoxy-hydroxide compositions, iron-rich clay and phyllosilicate minerals,and elemental iron.

Sorting 105 may also be used as a composition adjustment method 103 andany undesirable waste material may be discarded.

The resulting solid aluminosilicate material comprising a desirablecomposition is next heated 106. The heating is carried out to reach aheating temperature above a liquid phase temperature to obtain a liquid,for instance at about 1000-1600° C., or about 1300-1550° C. Any suitablemethod or apparatus may be used for the heating and for obtaining theliquid including, but not limited to, in-flight melting and/or batchmelting. This may be achieved by using, for instance, a plasma furnace,an oxy-fuel furnace, an arc furnace, a reverberatory furnace, a rotarykiln and/or a solar furnace. Typically, a furnace temperature of1000-1600° C. is needed, and most typically 1300-1550° C., to obtain thedesired liquid phase.

If desired, a fluxing material may be added to the solid aluminosilicatematerial to lower its melting point and/or to induce depolymerization ofthe liquid. The fluxing material may be mixed with the solidaluminosilicate material prior to heating (e.g. vessel) or during theheating. Common fluxing materials that may induce depolymerization inmelts, and/or lower melting temperature include CaF2, CaCO3, wasteglass, glass cullet, glass frit, alkali-bearing minerals (e.g.feldspars, zeolites, clays, and feldspathoid minerals), borate salts,halogen compounds (fluoride and chloride bearing salts) and calciumsalts.

Next, the aluminosilicate liquid is quenched 107 to obtain a solid. Inembodiments, the quenching step comprises reducing temperature of theliquid significantly below the glass transition, for instance at 500° C.or lower, or preferably below 200° C. or lower. In embodiments, thequenching is done rapidly, i.e. the temperature is reduced at a rate ofabout 10²-K^(s-1)-10⁶K^(s-1) (preferably at a rate of >10^(3.5)K^(s-1)). Any suitable method may be used for the quenching including,but not limited to, contacting the molten material with a sufficientstream of adequately cool air, with steam, or with water to produce anon-crystalline solid.

Next, the solid is crushed and/or pulverized in order to reduce particlesize 108 and obtain the cementitious reagent 109.This may be carried outusing any suitable method or apparatus including, but not limited to, aball mill, a roller mill and a vertical roller mill. Preferably theparticle size is reduced to obtain a fine powder useful in cementitiousapplications. In embodiments, the powder comprises a particle sizedistribution with D50 (median diameter) of approximately 20 82 m orless, or preferably 10 μm or less. Such a particle size is generallydesirable to ensure sufficient reactivity and consistent materialproperties.

Uses of the Cementitious Reagent

One related aspect concerns the broad relevance of the cementitiousreagent described herein. Appropriate compositions of engineeredcementitious reagent may be used interchangeably in significantproportion in both geopolymer cements and hydraulic cements (i.e.cements that react with water).

Accordingly, embodiments described herein encompass geopolymer cementsand hydraulic cements comprising at least 5 wt. %, or at least 10 wt. %,or at least 15 wt. %, or at least 20 wt. %, or at least 25 wt. %, or atleast 30 wt. %, or at least 40 wt. %, or at least 50 wt. %, or at least60 wt. %, or at least 70 wt. %, or at least 80 wt. %, or at least 90 wt.%, or more, of a cementitious reagent as described herein.

In accordance with another aspect, some embodiments relate to asupplementary cementitious material (SCM) comprising a cementitiousreagent as defined herein. In embodiments, the SCM comprises about 5 wt.% to about 50 wt. % (preferably at least 20 wt. %) of the cementitiousreagent as defined herein.

In accordance with another aspect, some embodiments relate to asupplementary cementitious material (SCM) comprising one or more of thefollowing properties: it comprises less than about 35 wt. % CaO, withappreciable content of Na/K (e.g. at least 2 wt. %, preferably at least5 wt. %) and Al content (e.g. at least 5 wt. %) and is in the form of anon-crystalline solid.

In accordance with another aspect, some embodiments relate to a solidconcrete, comprising a cementitious reagent as described herein, i.e.comprising about 5 wt. % to about 50 wt. % (preferably at least 20 wt.%) of the cementitious reagent as described herein.

In accordance with another aspect, some embodiments relate to a blendedhydraulic cement that is distinguishable from Portland cement. Forinstance, solid-state 29Si NMR spectroscopy can differentiate blendedhydraulic cement with low iron (<5 wt. %) according to the presentinvention from Portland cement (having dominant CSH binder constituent)by the amount and type of connectivity of silica tetrahedra in the curedcements. Indeed, cured Portland cement binder phases are characterizedby low coordination and hydrated sites (Q1, Q1(OH), Q2, and Q2(OH)),insignificant tetrahedral Al substitution, and no higher coordination(i.e. no Q3 and Q4 sites). The blended hydraulic cement withcementitious reagent according to the present invention will show thetypical CSH-related sites above in addition to unique features such as:aluminum substitution (e.g. Q2(1 Al)), and a “higher” level ofcoordination than Portland cement (i.e. branching). For instance, ablended hydraulic cement according to the present invention can compriseat least a Q3 level of coordination (e.g. (Q3(2 Al), Q3(1 Al), Q3(0Al)). In embodiments the blended hydraulic cement according to thepresent invention contains a measurable proportion (>1 wt. %) ofthree-dimensional cross-linking (Q4 sites) which is not known inconventional hydraulic cements. In accordance with another aspect, thepresent invention relates to a geopolymer binder comprising acementitious reagent as defined as defined herein, i.e. comprising about5 wt. % to about 90 wt. % (preferably at least 20 wt. %, at least 30 wt.%, at least 50 wt. %, at least 75 wt. %,) of the cementitious reagent asdefined herein.

In accordance with another aspect, some embodiments relate to solidgeopolymer concrete comprising about 5 wt. % to about 50 wt. %(preferably at least 20 wt. %) of the cementitious reagent as definedherein.

Those skilled in the art can appreciate that the present inventionadvantageously provides means to produce versatile low-CO₂ cementitiousreagents from abundant, cheap natural materials. Another significantadvantage is the creation of a single reagent that meets today'sspecification standards for alternative SCMs, while also meeting theneeds of the growing geopolymer market.

Aluminosilicate Materials

As described herein, some embodiments provide a method forthermochemical processing of aluminosilicate materials to produce asolid cementitious reagent that may advantageously be used as analternative supplementary cementitious material (SCM) in blendedhydraulic cement and/or as a geopolymer solid reagent in geopolymerbinders (thus eliminating the need for some or all of MK-750, fly ash,GGBFS, and other common solid reagents).

In some cases, an aluminosilicate material is used to produce anon-crystalline cementitious reagent as defined herein. In someembodiments, an aluminosilicate material is used to produce at least oneof a supplementary cementitious material (SCM) and a geopolymer reagent.

As used herein, the term “aluminosilicate material” refers to a materialcomprising aluminum and/or Fe3+, and silicon dioxide selected fromnatural rocks and minerals, dredged materials, mining waste comprisingrocks and minerals, waste glass, aluminosilicate-bearing contaminatedmaterials and aluminosiliceous industrial by- products. Analuminosilicate material according to the present invention ispreferably in the form of a crystalline solid (e.g. at least 50 wt. %,or at least 60 wt. %, or at least 70 wt. %, or at least 80 wt. %, or atleast 90 wt. %, or 100 wt. % crystalline solid). In embodiments, thealuminosilicate material comprises at least 2 wt. % (Na₂O,K₂O), or atleast 3 wt. % (Na₂O,K₂O), or at least 4 wt. % (Na₂O,K₂O), or at least 5wt. % (Na₂O,K₂O), at least 6 wt. % (Na₂O,K₂O), or at least 7 wt. %(Na₂O,K₂O), or at least 8 wt. % (Na₂O,K₂O), or at least 10 wt. %(Na₂O,K2O), or at least 12 wt. % (Na₂O,K₂O), or at least 15 wt. %(Na₂O,K2O), or at least 20 wt. % (Na₂O,K₂O).

In some embodiments, the aluminosilicate material is selected fromdredged sediments, demolished concrete, mine wastes, glacial clay,glacial deposits, fluvial deposits, rocks and mineral mixtures, forinstance rocks and mineral mixtures composed of some or all the elementsCa, Na, K, Fe, Al and Si.

In some embodiments, aluminosilicate materials are selected as afeedstock for producing cementitious reagent. The feedstock may beanalyzed by quantitative or semi-quantitative methods such as XRF, XRDwith Rietveld Refinement, LIBS, EDS, wet chemical analysis, and variousother existing methods to determine the feedstock elemental composition.

Example 10: Using Dredged Sediments

A sample of sediments was taken from the tidal lower reaches of theFraser River, Vancouver, BC. The sample is composed of fine sand, siltand clay size fractions. The mineralogy of the sample is given in Table19 (determined by XRD with Rietveld refinement) and the major elements'oxide composition was estimated from the mineralogy (Table 20).

TABLE 19 Mineralogy of Fraser River Sediment Sample Phase Weight %quartz-low 42 andesine 16 albite-low 13 illite/musc 2m1 11 clinochlore 5augite 4 orthoclase 4 actinolite 4 dolomite 2 kaolinite 2

TABLE 20 Oxide Composition (estimated from mineralogy) Oxide Weight %SiO2 73.0 Al2O3 11.9 Fe2O3 0.2 FeO 1.5 MnO 0.0 MgO 3.1 CaO 3.3 Na2O 2.6K2O 1.4 CO2 0.9 H2O 2.2

Fraser river sediment (FRS) was dried, classified, and the fractionpassing 120 μm was fed to a vitrification apparatus that heated thematerial through the melting point to approximately 1450° C., followedby a quenching step to cool the powder. The resulting FRS-glass powderwas ground in a ball mill to D50<20 μm. The X-ray amorphous component ofthe obtained powder was 52%. The mineralogy results yield an estimatedmolar Si/(Al, Fe³⁺) of 11.46, and molar cementitious reagent compositionof (Ca,Mg)_(1.25).(Na,K)_(0.34).(Al, Fe³⁺)₁.Si_(11.46) and CaO of 3.3wt. %. This may be qualified as a “low-Ca cementitious reagent”.

Heat-cured geopolymer binder: 5 parts of the low-Ca cementitious reagentwas mixed with 1 part potassium silicate solution (Molar ratioSi_(2:)K₂O=1.45). The paste was mixed thoroughly, placed in a sealedmold and cured at 80° C. for 4 hours. The resulting hardened pasteachieves at least 20 MPa compressive strength in a cylinder compressiontest.

Ambient-cured geopolymer binder: 5 parts of the low-Ca cementitiousreagent was mixed with 1 part potassium silicate solution (Molar ratioSi₂:K₂O=1.45), 1 part water, and 1.5 parts finely ground CaSiO_(3.) Thesilicate solution was mixed with the CaSiO₃ powder and allowed to reactfor 15 minutes. The resulting paste was mixed thoroughly with the FRSglass powder and water, then placed in a sealed mold and cured at 20° C.for 7 days. The resulting hardened paste achieves at least 20 MPacompressive strength in a cylinder compression test.

Ambient-cured SCM application in Portland Cement: a series of Portlandcement mortar cubes were cast from a 50:50 mix of cement and sand. Thelow-Ca cementitious reagent was substituted at 0%, 20%, 40%, 60% and 80%in place of Portland cement in the mortar mix. The cubes were cured for7 days at 100% humidity and the compressive strength of the cubes ispresented in Table 21. Up to 60% replacement of ordinary Portland cement(“OPC”) yields useable compressive strength for many applications whileproportionally reducing CO₂ footprint of the mortar.

TABLE 21 7-Day Compressive Strength, SCM Application FRS CementitiousReagent (%) Compressive Strength (MPa ± 10) 0% (100% OPC) 40 20% (80%OPC) 37.5 40% (60% OPC) 30 60% (40% OPC) 15 80% (20% OPC) 3.5

Example 11: Using Demolished Concrete

A core of structural concrete was sampled from a 2019 mid-rise housingdevelopment in Vancouver, BC. The mineral composition of the concrete(including fine and coarse aggregate) is given in Table 22 (XRD withRietveld refinement), and the bulk elemental composition is calculatedfrom the mineralogy in Table 23.

TABLE 22 Mineralogy of concrete sample Phase Weight % albite-low(calcian) 31 quartz-low 21 albite-low 11 orthoclase 8 calcite 8 *CSH gelestimate 6 clinozoisite 3 actinolite 3 clinochlore II 3 biotite 1M 2ettringite 2 C2S beta 2 brownmillerite (Al) 1 gypsum 1

TABLE 23 Oxide Composition (estimated from mineralogy) Oxide Weight %SiO₂ 64 Al₂O₃ 13 Fe₂O₃ 0 FeO 1 MnO 0 MgO 2 CaO 11 Na₂O 5 K₂O 2 CO₂ 4 H₂O4

The concrete was crushed and pulverized to a powder with D50 of about 20μm. The powder was fed through a vitrification apparatus that heated thematerial through the melting point to approximately 1450° C., followedby a quenching step. The resulting glassy particles were finely groundto a powder with D50 of approximately 5-15 μm.

The mineralogy results of this powder yield an estimated molar Si/(Al,Fe³⁺) of 9.88, and molar cementitious reagent composition of(Ca,Mg)_(2.79).(Na,K)_(0.55).(Al, Fe³⁺)₁.Si_(9.88) and CaO of 11 wt. %.This may be qualified as an “intermediate-Ca cementitious reagent”.

Ambient-cured geopolymer cement: Cement paste was thoroughly mixed byweight using the powdered concrete glass (2.5 parts), a potassiumsilicate solution with molar ratio SiO₂:K₂O=1.45 (0.74 parts), and water(0.08 parts). The paste was then placed in cylinder molds and cured at20° C. Setting time was estimated by Vicat needle penetration test.Initial setting occurred at 51 minutes, and final setting time was 195minutes.

Compressive strength of a mortar mix comprising 50:50 of theambient-cured geopolymer cement and sand was measured by compressingcylinders to failure. After 3 days, compressive strength attainedapproximately 25 MPa, and tensile strength was approximately 2 MPa (bysplit cylinder method).

To test high heat performance, a sample of the original structuralconcrete and a 1 cm diameter cast cylinder of geopolymer were subjectedto 750° C. in air for 2 hours. The Portland cement concrete decrepitatedand turned to powder upon handling, but the geopolymer mortar cylinderremained intact with no visible cracks or defects.

The novel methods, systems, apparatus, and formulations presented hereinprovide numerous benefits as detailed throughout. In some instances, thenovel formulation and processes result in a particle, powder, or reagentthat is particularly useful as a replacement for traditionalcementitious additives in hydraulic cement or geopolymer cementcompositions. The novel formulation may comprise a molar composition, inwhich:

$\frac{Si}{{Si} + {Al} + {Fe} + \left( {{Ca} + {Mg}} \right) + \left( {{Na} + K} \right)} = {0.295{to}{about}0.605}$$\frac{Al}{{Si} + {Al} + {Fe} + \left( {{Ca} + {Mg}} \right) + \left( {{Na} + K} \right)} = {0.19{to}{about}0.34}$$\frac{Fe}{{Si} + {Al} + {Fe} + \left( {{Ca} + {Mg}} \right) + \left( {{Na} + K} \right)} = {0{to}{about}0.16}$${\frac{{Ca} + {Mg}}{{Si} + {Al} + {Fe} + \left( {{Ca} + {Mg}} \right) + \left( {{Na} + K} \right)} = {0{to}{about}0.215}},{and}$$\frac{{Na} + K}{{Si} + {Al} + {Fe} + \left( {{Ca} + {Mg}} \right) + \left( {{Na} + K} \right)} = {0.04{to}{about}0.24}$

While the novel formulas presented herein result in a unique materialthat is especially suited for the purposes described throughout, it canbe difficult to differentiate the material by its individual elementalranges or a region on a ternary diagram alone, due to the fact thatternary diagrams are limited to visualization of exactly threecompositional parts and all the elemental parts of the total compositionhave interdependent relationships.

As geochemical compositions are classified as “compositional data,” atransformation (centered logratio transformation—CLR) from the Simplexto the Euclidean space was applied to the 7-part compositions,preserving the information encoded in molar compositions in a way thatstandard statistical methods can handle.

On the CFR representation of chemical data, a Random Forestclassification was completed, and from this predictive model, the 8-ruleclassification set (presented below) was extracted. Using this rule set,fly ash and the described feedstock compositions are separated, despitethe fact that there may appear to be compositional overlap between thesematerials on ternary diagrams. A classification model such as this isuseful to accurately represent or classify compositions exceeding3-dimensional data.

Modeling the Novel Formulation and Material

The described glassy reagent (“Novel Feedstock”, or alternativecementitious material “ACM”) is differentiated from fly ash in severalimportant characteristics, such as time-temperature history,manufacturability at nearly any location, and a relatively lower valuesof problematic heavy metal contaminants. Major element chemicalcomposition of embodiments described herein is also readilydifferentiated statistically from fly ash using compositional rules. Byway of example, a statistical model was built using fly ashcompositional data from the literature, and expected suitable feedstockcompositions as described herein. The classification rules weregenerated from a subsample as training data, and tested on remainingcompositions (fly ash, and the novel compositions described herein) toassess accuracy and predictive power of the classification rules. In themodel below, fly ash is predicted correctly 94% of the time on 331global compositions of fly ash from the literature, and the other 6%were classified as “outside the rule set”. No fly ash samples weremisclassified as the novel feedstock geological material describedherein. The model was applied to more than 70,000 compositions ofnatural geological materials that fit in the disclosed molar compositionrange, and the model predicts the novel feedstock described herein with99% success rate. Less than 1% of the compositions fell under thecategory of “outside the rule set”. Clearly there are significant andpredictable differences between the novel feedstocks described hereinand other by product reagents, such as fly ash. Composition alone,represented in centered log ratio coordinates (CLR) is highly accuratein discerning the chemistry of the described glassy particles from flyash.

Application of the Model

To apply the model below:

-   -   1. Measure bulk chemical composition of a given glassy sample by        any suitable analytical method and provide molar % of Si, Al,        Fe, Ca, Mg, Na and K.    -   2. Convert molar data to CLR coordinates for the 7 elements.    -   3. Apply the following conditions sequentially to predict        whether the sample is Fly Ash, or a Terra reagent, respectively.

Note: If a condition is not satisfied, apply next condition. If noconditions apply to given composition, ELSE predicts that the sample isoutside of the model's rule set and cannot be confidently predicted.

Rules

-   -   1. For glassy material with bulk CaO oxide equivalent wt. %        <35%, AND    -   2. Bulk mol % ratio Si/Al >2,

Notably, Rule 1 above can be used to rule out slag as a feedstock, andRule 2 can be used to rule out metakaolin, kaolinite, and other 1:1 clayrich feedstocks. Apply the following conditions to closed, CLRtransformed molar sample compositions using the logic IF (condition=TRUE), THEN (prediction), ELSE (move to next condition) as shown inTable 24 below:

TABLE 24 Condition Prediction Si > 0.40109 & Si <= 1.18718 & Al <=0.52677 & Novel Feedstock Al <= 0.40675 & Ca <= −0.40656 & Ca <= −0.7324Al > 0.5364 & Al > 0.55929 & Ca > −4.65173 & Fly Ash Na <= −1.2763 & Mg<= −0.7076 & K > −4.1446 Si > 0.43721 & Fe <= 0.31807 & Fe > −2.32162 &Novel Feedstock Ca <= −0.08759 & Mg > −1.80049 & Mg > −1.47036 Al <=0.52677 & Ca <= −0.31475 & K > −1.52367 Novel Feedstock Si <= 0.44413 &K <= −2.12091 Fly Ash Fe > −1.19597 & Ca <= −0.36227 & Na > −1.79741 &Novel Feedstock Na <= −0.18124 & Mg > −2.7976 & K <= −1.87031 Al >0.5364 & Fe > −2.59819 & Mg <= −0.7076 & Fly Ash Mg > −6.29972 & Mg <=−0.93309 & K > −4.10525 ELSE Outside rule set

FIG. 11 illustrates the region of the novel 7-part molar compositions ina complete set of ternary diagrams. The circled areas highlight thedifferences between the Novel Feedstock and global fly ash samples fromthe literature. Examples As illustrated, the top row of four ternarydiagrams represents the Si perspective, and is shown in more detail inFIG. 12 . With reference to FIGS. 11-15 , a black outline of samplesindicates the alternative cementitious material (“ACM”) describedherein, which may also be referred to as the Novel Feedstock. ACMCompositions of Examples 1-8 are shown as black dots labelled with thenumber corresponding to the example composition (numbers andcompositions summarized in Table 17). The grey outline shown in thefigures represents a 90% confidence interval of fly ash samples, basedon 331 unique samples (same as were categorized using the abovestatistical model).

The second row of figures in FIG. 11 represents ternary diagrams fromthe Al perspective, and is shown in further detail in FIG. 13 .

The third row of figures in FIG. 11 represents ternary diagrams from theFe perspective, and is shown in further detail in FIG. 14 .

Finally, the last row of FIG. 11 represents a ternary diagram from theCa+Mg perspective, and is shown in greater detail in FIG. 15 .

FIGS. 11-15 illustrate the Novel Feedstock as it relates to global flyash compositions and clearly shows that the two material populations arehighly distinguishable from each other even on elemental molar ternarydiagrams. The areas of apparent overlap between the Novel feedstock andfly ash are shown to be differentiated in the higher dimensionalclassification model provided herein. The Novel Feedstocks or ACMdescribed herein are not particularly alkali resistant and participatein a reaction with alkali hydroxides or lime as a reagent.

FIG. 16 illustrates a schematic flow diagram of the process 1600 ofmaking an alternative cement concrete using a relatively smalldecentralized in-flight minikiln. The minikiln can be located at anysuitable place, and because of the size and nature of the minikiln, isespecially suited to be collocated at an aggregate quarry, at a concretebatch plant, in-between a quarry and a concrete batch plant, or anyother suitable location to minimize, or at least reduce, thetransportation time and distance typically required for concrete batchplants relying on Portland cement.

At 1602, an aluminosilicate aggregate is provided, as described herein.The aggregate material may be any suitable aluminosilicate material, andmay be specifically mined for the intended purpose, or may be wastematerial, such as mine tailings, ground concrete, or some other type ofaggregate. At block 1604, the aluminosilicate material is milled to apowder, as described herein.

At block 1606, a milled aluminosilicate material may be stored, shipped,or provided to an input of a minikiln as described herein. At block1608, energy is added to the milled aluminosilicate aggregate, such ascombustion of an air/fuel mixture, a torch, industrial heat, or someother form of energy to increase the temperature of the aggregate. Insome embodiments, the aluminosilicate particles are optionally amended,blended (e.g. in a vessel prior to thermochemical processing), forexample, through addition of a composition adjustment material in orderto reach desired ratio(s) with respect to one or several of the elementsCa, Mg, Na, K, Al, Fe, and Si.

At block 1608, the energy causes the aluminosilicate aggregate to melt,which in some cases, occurs in-flight (at block 1610), such as where theaggregate is entrained within a column of air and/or air/fuel within amelting chamber.

At block 1612, after the aggregate is melted and quenched, the feedstockbecomes glassy aluminosilicate particles. In some cases, the particlesare substantially spheroidal with a roundness R>0.8.

At block 1614, the particles are combined with other ingredients at aconcrete batch mixing plant, which may be collocated with the minikilnin some instances. At block 1616, Additives may be added to theconcrete, such as hardener, ambient cure reagent, admixtures,plasticizers, reinforcement materials, and the like. At block 1618, sandand coarse aggregate may be added to the cement as is known in the art.

At block 1620, the final concrete mixture is formed and ready to beused.

According to some embodiments, a method of cement production decreasescement transportation distance (and therefore cost) compared toconventional methods. Some embodiments allow for decentralizedproduction of an Alternative Cement Material (ACM) in close proximity toan aluminosilicate aggregate quarry and a concrete batch plant. This ACMmay be advantageously used as a primary reagent in a suitablealternative cement formulation that can be used to make cost-effectiveand CO2-reduced concrete.

Alternatively, the ACM may be used as an alternative supplementarycementitious material (ASCM) to replace a proportion of Portland cementin conventional concrete and thereby reduce cost and environmentalimpact of resulting concrete.

FIG. 17 illustrates a typical Portland cement plant 1702 in which thecement may typically be shipped over long distances to reach concretebatch plants 1704. Similarly, aggregate from quarries 1706 may also beshipped long distances to reach their destination at concrete batchplants 1704. The time and energy to ship these dense and voluminousproducts dramatically increases the cost associated with manufacturingconcrete as well as contributes to the overall CO₂ emissions associatedwith concrete production.

FIG. 18 illustrates an alternative arrangement 1800 that utilizes theACM described herein. In some instances, an ACM minikiln 1802 can becollated at an aggregate quarry 1706 site. In this way, thealuminosilicate material mined at the aggregate quarry 1706 can beprocessed at the ACM minikiln 1802 on-site without transporting theaggregate to a remote location. The ACM and sufficient aggregate canthen be sent to the concrete batch plant 1704, which may be in muchcloser proximity.

FIG. 19 illustrated an alternative arrangement 1900 that utilizes theACM described herein. In the illustrated embodiment, and ACM minikiln1802 can be collocated with a concrete batch plant 1704. Accordinglyaggregate from an aggregate quarry 1706 can be delivered to the concretebatch plant 1802 and the aggregate can be used by the ACM minikiln 1802as described herein, and also be used as the coarse aggregate in theconcrete mix.

FIG. 20 illustrates an alternative arrangement 2000 that utilizes theACM described herein. In the illustrated embodiment, an ACM minikiln1802 is located between an aggregate quarry 1706 and a concrete batchplant 1704. In this arrangement, aggregate can be delivered to the ACMminikiln, which utilizes the aggregate to formulate ACM as describedherein, and the ACM and additional aggregate can be shipped to aconcrete batch plant.

The minikiln architecture allows a distributed system that takesadvantage of the smaller, and even portable nature, of the ACM minikiln.Rather than relying on a single centralized Portland cement plant thatmust ship cement long distances, a number of ACM minikilns can replace aPortland cement plant and reduce shipping times and costs dramatically.The illustrated embodiments of FIGS. 17-20 offer an architecture that isnimble, efficient, and reduces waste by locating the ACM minikiln inclose proximity to the aggregate quarry, the concrete batch plant, orboth.

Suitable feedstock compositions and the process of converting thefeedstock to microspheroidal glassy particles have been disclosed inApplicant's copending applications having Ser. No. 62/867,480, filed onJun. 27, 2019 and Ser. No. 63/004,673, filed Apr. 3, 2020, the entiredisclosures of which are hereby incorporated by reference in theirentirety. Suitable feedstocks are generally rocks and minerals bearing aproportion of both aluminum and silicon oxides. Ordinary constructionaggregate materials used in concrete are suitable, economic, andconveniently located for use as an ideal cement feedstock. Previously,it was not possible to make a cementitious material from such ordinarycrystalline aluminosilicate materials.

One particular advantage of using aluminosilicate aggregate as ACMfeedstock is that the material is cheaply and abundantly available.

Another particular advantage is that aluminosilicate aggregate quarriesexist widely, and generally there is no need for permitting of newquarries to make ACM by the present method in most markets.

Another particular advantage of using aluminosilicate aggregate as ACMfeedstock is that a minikiln (for example as described in Applicant'scopending application having Ser. No. 63/004,673) may be collocated ator very near the aggregate quarry, or concrete batch plant, or both,thus minimizing transportation costs of cement. This great advantagecomes about because cement from large centralized kilns travels onaverage 5-10 times further than aggregate (supply of which isdecentralized); a natural consequence of widespread aggregateavailability, low price of aggregate, and high price of shippingaggregate.

Another particular advantage of using aluminosilicate aggregate as ACMfeedstock is that frequently quarries have abundant byproduct materialavailable that is “off-specification”, meaning that there is no commonuse for that particular gradation, despite such materials sharinggenerally identical composition with the main quarry products. Suchbyproduct materials are very cheaply available at both crushed stoneaggregate quarries, as well as sand and gravel quarries.

Another particular advantage of the decentralized ACM minikilns is thatcapital cost per unit of throughput is expected to be similar toconventional rotary cement kilns, though the absolute scale of capitalrequirement is on the order of 1/10^(th) what it would be for Portlandcement production.

Another particular advantage of the decentralized ACM minikilns is thatoperating expenditures per unit of throughput are not expected to exceedthe corresponding expenses in manufacture of Portland cement. Thereby,ACM production is cost-competitive with Portland cement at a smallerscale of production, yet requires 5-10 times less shipping expense.

The present disclosure includes the following numbered clauses.

Clause 1. Solid microspheroidal glassy particles, wherein said particlescomprise one or more of the following properties: mean roundness (R)>0.8; and less than about 40% particles having angular morphology (R<0.7).

Clause 2. The particles of clause 1, wherein said particles comprise amean roundness (R) of at least 0.9.

Clause 3 The particles of clause 1 or 2, wherein less than about 30%particles, or less than about 25% particles, or less than about 20%particles, or less than about 15% particles, or less than about 10%particles have an angular morphology (R<0.7).

Clause 4. The particles of any one of clause 1 to 3, wherein saidparticles comprise the mean oxide Formula 1:(CaO,MgO)a.(Na₂O,K₂O)b.(Al₂O₃, Fe₂O₃)c.(SiO₂)d  [Formula 1]wherein a is about 0 to about 4, b is about 0.1 to about 1, c is 1, andd is about 1 to about 20.

Clause 5. The particles of any one of clauses 1 to 4, wherein saidparticles comprise one or more of the following properties: (i) acontent of 45%-100%, and preferably 90-100%, X-ray amorphous solid; and(ii) molar composition ratios of (Ca,Mg)₀₋₁₂.(Na,K)_(0.05-1).(Al,Fe³⁺)₁.Si₁₋₂₀.

Clause 6. The particles of any one of clauses 1 to 5, wherein saidparticles are 40-100% X-ray amorphous, more preferably about 80- about100% X-ray amorphous, even more preferably 100% non-crystalline.

Clause 7. The particles of any one of clauses 1 to 6, wherein saidparticles comprise less than about 10 wt. % CaO.

Clause 8. The particles of any one of clauses 1 to 6, wherein saidparticles comprise more than about 30 wt. % CaO.

Clause 9. The particles of any one of clauses 1 to 6, wherein saidparticle comprises a high-calcium content with a molar composition ofSi/(Fe3+,Al) between 1-20, and CaO content of about 10- about 50 wt. %,preferably about 20-45 wt. %.

Clause 10. The particles of any one of clauses 1 to 6, wherein saidparticle comprises an intermediate-calcium content with a molarcomposition of Si/(Fe3+,Al) between 1-20, and CaO content of about 10-about 20 wt. %.

Clause 11. A cementitious reagent comprising a mixture ofmicrospheroidal glassy particles as defined in any one of clauses 1 to10.

Clause 12. A cementitious reagent comprising a mixture ofmicrospheroidal glassy particles, wherein said particles comprises oneor more of the following properties: (i) mean roundness (R)>0.8; (ii)less than about 20% particles having angular morphology (R<0.7); (iii)the oxide Formula 1 as defined in clause 4; (iv) a content of 45%-100%,and preferably 90-100%, X-ray amorphous solid; and (v) a molarcomposition ratios of (Ca,Mg)₀₋₁₂.(Na,K)_(0.05-1).(Al, Fe³⁺)₁Si₁₋₂₀; and(vi) a low calcium content of about <10 wt % CaO, or an intermediatecalcium content of about 10 to about 20% wt % CaO, or a high calciumcontent of >30wt % CaO.

Clause 13. The cementitious reagent of clause 12, wherein saidcementitious reagent is in the form of a non-crystalline solid.

Clause 14. The cementitious reagent of clause 12 or 13, wherein saidcementitious reagent is in the form of a powder.

Clause 15. The cementitious reagent of any one of clauses 12 to 14,wherein said cementitious reagent comprises particle size distributionwith D[3,2] of about 20 μm or less, more preferably 10 μm or less, ormost preferably 5 μm or less.

Clause 16. The cementitious reagent of any one of clauses 12 to 15,wherein said mixture of particles comprises the oxide Formula 1:(CaO,MgO)a.(Na₂O,K₂O)b.(Al₂O₃,Fe₂O₃)c.(SiO₂)d  [Formula 1]wherein a is about 0 to about 4, b is about 0.1 to about 1, c is 1, andd is about 1 to about 20.

Clause 17. The cementitious reagent of any one of clauses 12 to 16,wherein said cementitious reagent comprises less than about 10 wt. %CaO.

Clause 18. The cementitious reagent of any one of clauses 12 to 16,wherein said cementitious reagent comprises more than about 30 wt. %CaO.

Clause 19. The cementitious reagent of any one of clauses 12 to 16,wherein the cementitious reagent is a high-calcium containingcementitious reagent with a molar composition of Si/(Fe³⁺,Al) between1-20, and CaO content of about 10- about 50 wt. %, preferably about20-45 wt. %.

Clause 20. The cementitious reagent of any one of clauses 12 to 16,wherein the cementitious reagent is an intermediate-calcium containingcementitious reagent with a molar composition of Si/(Fe³⁺,Al) between1-20, and CaO content of about 10- about 20 wt. %.

Clause 21. The cementitious reagent of any one of clauses 12 to 20,wherein the cementitious reagent is about 40-100% and preferably about80- about 100% X-ray amorphous, and even more preferably 100%non-crystalline.

Clause 22. A geopolymer binder comprising a cementitious reagent asdefined in any one of clauses 11 to 21.

Clause 23. A supplementary cementitious material (SCM) comprising acementitious reagent as defined in any one of clauses 11 to 21.

Clause 24. The SCM of clause 23, comprising at least 20 wt. % of saidcementitious reagent.

Clause 25. A solid concrete, comprising a cementitious reagent asdefined in any one of clauses 11 to 20.

Clause 26. Use of the microspheroidal glassy particles as defined in anyone of clauses 1 to 10 and/or of the cementitious reagent of any one ofclauses 11 to 20, to manufacture a geopolymer binder or cement, ahydraulic cement, a supplementary cementitious material (SCM) and/orsolid concrete.

Clause 27. A method for producing a cementitious reagent fromaluminosilicate materials, comprising the steps of: (i) providing asolid aluminosilicate material; (ii) in-flight melting/quenching saidsolid aluminosilicate material to melt said material into a liquid andthereafter to quench said liquid to obtain a molten/quenched powdercomprising solid microspheroidal glassy particles; thereby obtaining acementitious reagent with said powder of microspheroidal glassyparticles.

Clause 28. The method of clause 27, wherein said method furthercomprises step (iii) of grinding said powder of microspheroidal glassyparticles into a finer powder.

Clause 29. The method of clauses 27 or 28, wherein said powder comprisesparticle size distribution with D[3,2] of about 20 μm or less, morepreferably 10 μm or less, or most preferably 5 μm or less.

Clause 30. The method of any one of clauses 27 to 29, wherein saidparticles comprise one or more of the following properties: a meanroundness (R) of at least 0.7; less than about 20% particles of angularmorphology; the oxide Formula 1 as defined in clause 4; a content of45%-100%, and preferably 90-100%, X-ray amorphous solid; molarcomposition ratios of (Ca,Mg)₀₋₁₂.(Na,K)_(0.05-1).(Al, Fe³⁺)₁.Si₁₋₂₀;and a calcium content of less than about 10 wt. % CaO.

Clause 31. The method of any one of clauses 27 to 30, wherein saidcementitious reagent comprises one or more of the following properties:is reactive in cementitious systems and/or in geopolymeric systems;delivers workable low yield stress geopolymer cement mixes below 25 Pawhen a cement paste has an oxide mole ratio of H₂O(Na₂O,K₂O)<20];requires water content in cement paste such that the oxide mole ratioH₂O(Na₂O,K₂O)<20; and delivers a cement paste with higher workabilitythan an equivalent paste with substantially angular morphology, giventhe same water content.

Clause 32. The method of any one of clauses 27 to 31, further comprisingthe step of adjusting composition of a non-ideal solid aluminosilicatematerial to a desired content of thehd elements Ca, Mg, Na, K, Al, Fe,and Si.

Clause 33. The method of clause 32, wherein said adjusting comprisesblending said non-ideal aluminosilicate material with a compositionadjustment material in order to reach desired ratio(s) with respect toone or several of the elements Ca, Mg, Na, K, Al, Fe, and Si.

Clause 34. The method of any one of clauses 27 to 33, further comprisingthe step of sorting said solid aluminosilicate material to obtain apowder of aluminosilicate particles of a desired size.

Clause 35. The method of any one of clauses 27 to 34, further comprisingthe step of discarding undesirable waste material from said solidaluminosilicate material.

Clause 36. The method of any one of clauses 27 to 35, wherein saidin-flight melting comprises heating at a temperature above a liquidphase temperature to obtain a liquid.

Clause 37. The method of clause 36, wherein said temperature is about1000-1600° C., or about 1300-1550° C.

Clause 38. The method of any one of clauses 27 to 37, further comprisingadding a fluxing material to the solid aluminosilicate material to lowerits melting point and/or to induce greater enthalpy, volume, ordepolymerization of said liquid.

Clause 39. The method of clause 38, wherein the fluxing material ismixed with said solid aluminosilicate material prior to, or during saidmelting.

Clause 40. The method of any one of clauses 27 to 39, wherein saidin-flight melting/quenching comprises reducing temperature of saidliquid below temperature of glass transition to achieve a solid.

Clause 41. The method of clause 40, wherein said in-flightmelting/quenching comprises reducing temperature of said liquid belowabout 500° C., or preferably below about 200° C. or lower.

Clause 42. The method of clause 41, wherein reducing temperature of saidliquid comprises quenching at a rate of about 10² K^(s-1) to about 10⁶K^(s-1), preferably at a rate of>10^(3.5) K^(s-1).

Clause 43. The method of clause 41, wherein quenching comprises a streamof cool air, steam, or water.

Clause 44. The method of any one of clauses 27 to 43, further comprisingreducing particle size of said powder of solid microspheroidal glassyparticles.

Clause 45. The method of clause 44, wherein reducing particle sizecomprises crushing and/or pulverizing said powder in any one of a ballmill, a roller mill, a vertical roller mill.

Clause 46. The method of any one of clauses 27 to 45, further comprisingseparating quenched solid particles from hot gases in a cycloneseparator.

Clause 47. An apparatus for producing microspheroidal glassy particles,comprising: a burner; a melting chamber; and a quenching chamber.

Clause 48. The apparatus of clause 47, wherein the melting chamber andthe quenching chamber are first and second sections of the same chamber,respectively.

Clause 49. The apparatus of clauses 47 or 48, wherein said apparatus isconfigured such that solid particles are flown in suspension, melted insuspension, and then quenched in suspension in said apparatus.

Clause 50. The apparatus of any one of clauses 47 to 49, wherein saidburner provides a flame heating solid particles in suspension to aheating temperature sufficient to substantially melt said solidparticles into a liquid.

Clause 51. The apparatus of any one of clauses 47 to 50, wherein saidburner comprises a flame that is fueled with a gas that entrainsaluminosilicate feedstock particles towards the melt/quench chamber.

Clause 52. The apparatus of clause 51, wherein the gas comprises anoxidant gas and a combustible fuel.

Clause 53. The apparatus of any one of clauses 47 to 52, wherein saidthe quenching chamber comprises a cooling system for providing cool airinside the quenching chamber, said cool air quenching molten particlesto solid microspheroidal glassy particles.

Clause 54. The apparatus of clause 53, wherein said a cooling systemcomprises a liquid cooling loop positioned around the quenching chamber.

Clause 55. The apparatus of any one of clauses 47 to 54, wherein theapparatus further comprises a cyclone separator to collectmicrospheroidal glassy particles.

Clause 56. The apparatus of any one of clauses 47 to 55, wherein theburner comprises at least one of a plasma torch, an oxy-fuel burner, anair-fuel burner, a biomass burner, and a solar concentrating furnace.

Clause 57. A method for producing a cementitious reagent fromaluminosilicate materials, comprising the steps of: (i) providing asolid aluminosilicate material; (ii) in-flight melting/quenching saidsolid aluminosilicate material to melt said material into a liquid andthereafter to quench said liquid to obtain a molten/quenched powdercomprising solid microspheroidal glassy particles; thereby obtaining acementitious reagent with said powder of microspheroidal glassyparticles.

Clause 58. A method for producing microspheroidal glassy particles,comprising the steps of: providing an in-flight melting/quenchingapparatus, said apparatus comprising a burner, a melting chamber and aquenching chamber; providing solid particles; flowing said solidparticles in suspension in a gas to be burned by said burner; heatingsaid solid particles into said melting chamber to a heating temperatureabove liquid phase to obtain liquid particles in suspension; quenchingsaid liquid particles in suspension to a cooling temperature belowliquid phase to obtain a powder comprising solid microspheroidal glassyparticles.

Clause 59. The method of clause 58, wherein the melting chamber and thequenching chamber are first and sections of the same chamber,respectively.

Clause 60. The method of clauses 58 or 59, wherein said heatingtemperature is about 1000-1600° C., or about 1300-1550° C.

Clause 61. The method of any one of clauses 58 to 60, wherein coolingtemperature is below 500° C., or below 200° C.

Clause 62. The method of any one of clauses 58 to 61, wherein said solidparticles comprise aluminosilicate materials.

Clause 63. The method of any one of clauses 58 to 62, wherein saidburner comprises a flame that is fueled with a gas that entrains thesolid particles towards the melting chamber.

Clause 64. The method of clause 63, wherein the gas comprises an oxidantgas and a combustible fuel.

Clause 65. The method of any one of clauses 58 to 64, wherein saidquenching comprises providing cool air inside the quenching chamber.

Clause 66. The method of any one of clauses 58 to 65, further comprisingcollecting said powder with a cyclone separator.

Clause 67. Use of an apparatus comprising at least one of a plasmatorch, an oxy-fuel burner, an air-fuel burner, a biomass burner, and asolar concentrating furnace, for producing microspheroidal glassyparticles.

Clause 68. Use of an apparatus comprising at least one of a plasmatorch, an oxy-fuel burner, an air-fuel burner, a biomass burner, and asolar concentrating furnace, for producing a cementitious reagent fromaluminosilicate materials

Clause 67. All novel compounds, compositions, processes, apparatuses,systems methods and uses substantially as hereinbefore described withparticular references to the Examples and the Figures.

Headings are included herein for reference and to aid in locatingcertain sections. These headings are not intended to limit the scope ofthe concepts described therein, and these concepts may haveapplicability in other sections throughout the entire specification.Thus, the present invention is not intended to be limited to theembodiments shown herein but is to be accorded the widest scopeconsistent with the principles and novel features disclosed herein.

The singular forms “a”, “an” and “the” include corresponding pluralreferences unless the context clearly dictates otherwise. Thus, forexample, reference to “a solid microspheroidal glassy particle” includesone or more of such particle, and reference to “the method” includesreference to equivalent steps and methods known to those of ordinaryskill in the art that could be modified or substituted for the methodsdescribed herein.

Unless otherwise indicated, all numbers expressing quantities ofingredients, reaction conditions, concentrations, properties, and soforth used in the specification and claims are to be understood as beingmodified in all instances by the term “about”. At the very least, eachnumerical parameter should at least be construed in light of the numberof reported significant digits and by applying ordinary roundingtechniques. Accordingly, unless indicated to the contrary, the numericalparameters set forth in the present specification and attached claimsare approximations that may vary depending upon the properties sought tobe obtained. Notwithstanding that the numerical ranges and parameterssetting forth the broad scope of the embodiments are approximations, thenumerical values set forth in the specific examples are reported asprecisely as possible. Any numerical value, however, inherently containscertain errors resulting from variations in experiments, testingmeasurements, statistical analyses and such.

It is understood that the examples and embodiments described herein arefor illustrative purposes only and that various modifications or changesin light thereof will be suggested to persons skilled in the art and areto be included within the present invention and scope of the appendedclaims. A person of ordinary skill in the art will recognize that anyprocess or method disclosed herein can be modified in many ways. Theprocess parameters and sequence of the steps described and/orillustrated herein are given by way of example only and can be varied asdesired. For example, while the steps illustrated and/or describedherein may be shown or discussed in a particular order, these steps donot necessarily need to be performed in the order illustrated ordiscussed.

The various exemplary methods described and/or illustrated herein mayalso omit one or more of the steps described or illustrated herein orcomprise additional steps in addition to those disclosed. Further, astep of any method as disclosed herein can be combined with any one ormore steps of any other method as disclosed herein.

Unless otherwise noted, the terms “connected to” and “coupled to” (andtheir derivatives), as used in the specification and claims, are to beconstrued as permitting both direct and indirect (i.e., via otherelements or components) connection. In addition, the terms “a” or “an,”as used in the specification and claims, are to be construed as meaning“at least one of.” Finally, for ease of use, the terms “including” and“having” (and their derivatives), as used in the specification andclaims, are interchangeable with and shall have the same meaning as theword “comprising.

The processor as disclosed herein can be configured with instructions toperform any one or more steps of any method as disclosed herein.

As used herein, the term “or” is used inclusively to refer items in thealternative and in combination.

As used herein, characters such as numerals refer to like elements.

Embodiments of the present disclosure have been shown and described asset forth herein and are provided by way of example only. One ofordinary skill in the art will recognize numerous adaptations, changes,variations and substitutions without departing from the scope of thepresent disclosure. Several alternatives and combinations of theembodiments disclosed herein may be utilized without departing from thescope of the present disclosure and the inventions disclosed herein.Therefore, the scope of the presently disclosed inventions shall bedefined solely by the scope of the appended claims and the equivalentsthereof.

What is claimed is:
 1. A method comprising: introducing solid particlesof an aluminosilicate feedstock into a melt chamber; heating thealuminosilicate feedstock particles within the melt chamber to formmolten particles; and cooling the molten particles within a quenchchamber to form microspheroidal glassy particles, wherein themicrospheroidal glassy particles have a mean roundness (R) >0.7, and amolar composition containing Si and Al and optionally one or more of Fe,Ca, Mg, Na, and K, such that:${{{about}0.067} < \frac{Si}{{Si} + {A1} + {Fe} + {Ca} + {Mg} + {Na} + K} < {{about}0.95}};{and}$${{about}0} < \frac{Al}{{Si} + {Al} + {Fe} + {Ca} + {Mg} + {Na} + K} < {{about}{0.488.}}$2. The method of claim 1, wherein the aluminosilicate feedstock issubstantially free of fly ash.
 3. The method of claim 1, furthercomprising blending the aluminosilicate feedstock with a compositionadjustment material prior to heating the aluminosilicate feedstockparticles within the melt chamber.
 4. The method of claim 1, furthercomprising blending the aluminosilicate feedstock with a compositionadjustment material while heating the aluminosilicate feedstockparticles within the melt chamber.
 5. The method of claim 1, furthercomprising milling the solid aluminosilicate feedstock particles priorto heating the aluminosilicate feedstock particles within the meltchamber.
 6. The method of claim 1, further comprising mixing thealuminosilicate feedstock with a fluxing material adapted to lower amelting point of the aluminosilicate feedstock particles prior toheating the aluminosilicate feedstock particles within the melt chamber.7. The method of claim 1, further comprising entraining the solidaluminosilicate feedstock particles in a gas stream.
 8. The method ofclaim 7, wherein the gas stream comprises an oxidant gas and acombustible fuel.
 9. The method of claim 1, wherein the aluminosilicatefeedstock particles are suspended in a flame comprising an oxidant gasand a combustible fuel.
 10. The method of claim 9, wherein the flame isstabilized by an annular flow of quench air.
 11. The method of claim 1,wherein the solid aluminosilicate feedstock particles are flown andmelted in suspension and the molten particles are cooled in suspension.12. The method of claim 1, wherein the molten feedstock particles arecooled at a cooling rate of about 10² Ks⁻¹ to about 10⁶ Ks⁻¹.
 13. Themethod of claim 1, wherein the cooling comprises contacting the moltenparticles with a stream containing a fluid selected from the groupconsisting of air, steam, and water.
 14. The method of claim 1, furthercomprising milling the microspheroidal glassy particles to a Sauter meandiameter D[3,2] of about 20 micrometers or less.
 15. The method of claim1, wherein the microspheroidal glassy particles are at least about 40%x-ray amorphous.
 16. The method of claim 1, further comprisingcollecting the microspheroidal glassy particles using a cycloneseparator.
 17. The method of claim 1, further comprising mixing themicrospheroidal glassy particles with one or more additives selectedfrom the group consisting of hardeners, ambient cure reagents,admixtures, plasticizers, reinforcement materials, sand, and coarseaggregate.
 18. The method of claim 1, wherein the microspheroidal glassyparticles include Fe such that:$0 < \frac{Fe}{{Si} + {Al} + {Fe} + {Ca} + {Mg} + {Na} + K} < {0.488.}$19. The method of claim 1, wherein the microspheroidal glassy particlesinclude Ca and Mg such that:$0 < \frac{{Ca} + {Mg}}{{Si} + {Al} + {Fe} + {Ca} + {Mg} + {Na} + K} < {0.854.}$20. The method of claim 1, wherein the microspheroidal glassy particlesinclude Na and K such that:${{0.0}015} < \frac{{Na} + K}{{Si} + {Al} + {Fe} + {Ca} + {Mg} + {Na} + K} < {0.33.}$